Warning: linear constraint 0 and linear constraint 1 have the same name "Resourcebalane [1,0]"

import numpy as np
import pandas as pd
import xlrd
import csv
from collections import OrderedDict
import math

import gurobipy as gp
from gurobipy import GRB

group2heats = {'1': [1, 2, 3, 4], '2': [5, 6, 7, 8], '3': [9, 10, 11, 12],
               '4': [13, 14, 15, 16, 17], '5': [18, 19, 20], '6': [21, 22, 23, 24]}

equip2mw = {'EAF': 85, 'AOD': 2, 'LF': 2, 'CC1': 7, 'CC2': 7}

energy_price = [33.28, 30.00, 29.15, 28.49, 34.66, 50.01,  #14 sept nord pool day ahead SE1
                71.52, 77.94, 81.97, 87.90, 92.76, 94.98,
                92.31, 90.03, 90.09, 87.44, 85.37, 79.97,
                79.92, 77.83, 76.28, 65.06, 53.07, 34.16]

equip2process_time = {
                      'EAF1':{'1':80.0,'2':80.0,'3':80.0,'4':80.0,'5':85.0,'6':85.0,'7':85.0,'8':85.0,'9':90.0,'10':90.0,'11':90.0,'12':90.0,'13':85.0,'14':85.0,'15':85.0,'16':85.0,'17':80.0,'18':80.0,'19':80.0,'20':80.0,'21':80.0,'22':80.0,'23':80.0,'24':80.0},
                      'EAF2':{'1':80.0,'2':80.0,'3':80.0,'4':80.0,'5':85.0,'6':85.0,'7':85.0,'8':85.0,'9':90.0,'10':90.0,'11':90.0,'12':90.0,'13':85.0,'14':85.0,'15':85.0,'16':85.0,'17':80.0,'18':80.0,'19':80.0,'20':80.0,'21':80.0,'22':80.0,'23':80.0,'24':80.0},
                      'AOD1':{'1':75.0,'2':75.0,'3':75.0,'4':75.0,'5':80.0,'6':80.0,'7':80.0,'8':80.0,'9':95.0,'10':95.0,'11':95.0,'12':95.0,'13':85.0,'14':85.0,'15':85.0,'16':85.0,'17':85.0,'18':95.0,'19':95.0,'20':95.0,'21':80.0,'22':80.0,'23':80.0,'24':80.0},
                      'AOD2':{'1':75.0,'2':75.0,'3':75.0,'4':75.0,'5':80.0,'6':80.0,'7':80.0,'8':80.0,'9':95.0,'10':95.0,'11':95.0,'12':95.0,'13':85.0,'14':85.0,'15':85.0,'16':85.0,'17':85.0,'18':95.0,'19':95.0,'20':95.0,'21':80.0,'22':80.0,'23':80.0,'24':80.0},
                      'LF1':{'1':35.0,'2':35.0,'3':35.0,'4':35.0,'5':45.0,'6':45.0,'7':20.0,'8':20.0,'9':45.0,'10':45.0,'11':45.0,'12':45.0,'13':25.0,'14':25.0,'15':25.0,'16':25.0,'17':25.0,'18':45.0,'19':45.0,'20':30.0,'21':30.0,'22':30.0,'23':30.0,'24':30.0},
                      'LF2':{'1':35.0,'2':35.0,'3':35.0,'4':35.0,'5':45.0,'6':45.0,'7':20.0,'8':20.0,'9':45.0,'10':45.0,'11':45.0,'12':45.0,'13':25.0,'14':25.0,'15':25.0,'16':25.0,'17':25.0,'18':45.0,'19':45.0,'20':30.0,'21':30.0,'22':30.0,'23':30.0,'24':30.0},
                      'CC1':{'1':50.0,'2':50.0,'3':50.0,'4':50.0,'5':60.0,'6':60.0,'7':55.0,'8':55.0,'9':60.0,'10':60.0,'11':60.0,'12':60.0,'13':70.0,'14':70.0,'15':75.0,'16':75.0,'17':75.0,'18':60.0,'19':70.0,'20':70.0,'21':50.0,'22':50.0,'23':50.0,'24':50.0},
                      'CC2':{'1':50.0,'2':50.0,'3':50.0,'4':50.0,'5':60.0,'6':60.0,'7':55.0,'8':55.0,'9':60.0,'10':60.0,'11':60.0,'12':60.0,'13':70.0,'14':70.0,'15':75.0,'16':75.0,'17':75.0,'18':60.0,'19':70.0,'20':70.0,'21':50.0,'22':50.0,'23':60.0,'24':60.0}
                     }
stage2units = {'1': {'EAF': 2}, '2': {'AOD': 2}, '3': {'LF': 2}, '4': {'CC1': 1, 'CC2': 1}}

trans_time = {'TR_S1': 10, 'TR_S2': 4, 'TR_S3': 10}

trans_time_max = {'TR_S1': 240, 'TR_S2': 240, 'TR_S3': 120}

setup_time = {'CC1': 70, 'CC2': 50}

equip2process_time['EAF'] = equip2process_time.pop('EAF1')
equip2process_time.pop('EAF2')
equip2process_time['AOD'] = equip2process_time.pop('AOD1')
equip2process_time.pop('AOD2')
equip2process_time['LF'] = equip2process_time.pop('LF1')
equip2process_time.pop('LF2')
model = 'rtn1'                     
  
rtn_t0 = 15   

price_energy = []
for price in energy_price:
    price_energy = price_energy + [int(price)] * int(60 / rtn_t0) #prices for 96 time slots
num_t = 24 * 60 / rtn_t0 #total no of time slots i.e 96
num_stage = len((stage2units).keys()) #total no of stages i.e 4
num_groups = len((group2heats).keys()) #total no of groups i.e 6
num_heats = 0
for group, heats in group2heats.items():
    num_heats += len(heats) #total no of heats i.e 24


equip2num = {} #calculating each eqipment has how many units
for unit2num in stage2units.values():
    for unit, num in unit2num.items():
        equip2num[unit] = num

res_cat2idx = OrderedDict()
r_idx = 1

# equipment resources #creating a ordered dict where at 1st position there is resource EAF, 2nd position there is resource AOD , 3rd position there is resource LF, 4th position there is resource CC1, 5th position there is resource CC2
for stage in range(1, num_stage + 1):
    for unit in (stage2units)[str(stage)].keys():
        res_cat2idx[unit] = [r_idx]
        r_idx = r_idx + 1
        
# intermediate products and final products, A - after, B - before
for stage in range(1, num_stage+1):
    res_cat2idx['H_A_S%s' % stage] = range(r_idx, r_idx + num_heats) #'H_A_S1'=EAd1 (after stage1) 'H_B_S4'=EAs4(before stage4) #'H_A_S4'=intermediate product after stage 4 i.e final products heats
    r_idx = r_idx + num_heats
    if int(stage) == 1:
        continue
    res_cat2idx['H_B_S%s' % stage] = range(r_idx, r_idx + num_heats)
    r_idx =r_idx + num_heats
    
    
# energy resource
res_cat2idx['EN'] = [r_idx]
res_num = r_idx

[res_cat2idx, res_num] 

tasks = OrderedDict()
i_idx = 1

for stage in range(1,num_stage + 1): #calculates in order how many processing and transfer tasks are there. task_num is 156 for only 3 stages.(24 heats * 6 types of tasks for 3 stages(3 processsng and 3 transfer))
    for unit in (stage2units)[str(stage)].keys(): #CC1 and CC2 tasks are not counted in task_num
        if int(stage) == 4:
            tasks[unit] = range(i_idx, i_idx + num_groups)
            i_idx = i_idx + num_groups
        else:
            tasks[unit] = range(i_idx, i_idx + num_heats)
            i_idx = i_idx + num_heats
            tasks['TR_S%s' % stage] = range(i_idx, i_idx + num_heats)
            i_idx =i_idx + num_heats
    task_num = i_idx - 1
            
[tasks, task_num]

task_duration = dict()
task_cleanup_duration = dict()

for heat in range(1, num_heats + 1): #for heat 1, EAF,AOD,LF,TR_S1,TR_S2,TR_S3 , similar for heat 2...so on...
    for task_type in ['EAF', 'AOD', 'LF']:
        task_duration[tasks[task_type][heat - 1]]=int(math.ceil(float((equip2process_time)[task_type][str(heat)])/rtn_t0))
    for task_type in ['TR_S1', 'TR_S2', 'TR_S3']:
        task_duration[tasks[task_type][heat - 1]]=int(math.ceil(float((trans_time)[task_type])/rtn_t0))
        
for group in range(1, num_groups + 1):
    for task_type in ['CC1', 'CC2']:
        cast_time = [(equip2process_time)[task_type][str(heat)] for heat in group2heats[str(group)]]
        total_time = float(sum(cast_time))
        task_duration[tasks[task_type][group - 1]] = int(math.ceil(total_time/rtn_t0))
        total_time = float(sum(cast_time) + setup_time[task_type])
        task_cleanup_duration[tasks[task_type][group - 1]] = int(math.ceil(total_time/rtn_t0))
            
task_duration,task_cleanup_duration  


rtn_profile = dict()
for res_category, res_idxes in res_cat2idx.items(): #resources=res_cat2idx,created 174 blank dictionaries for 174 res_num
    for res_idx in res_idxes:
        rtn_profile[res_idx] = dict()

# equipment usage 
for stage in range(1, num_stage + 1): 
    for unit in (stage2units)[str(stage)].keys(): #[RESOURCE][TASK]'[1][1-25]'(EAF) , '[2][49-73]'(AOD) ,'[3][97-121]'(LF),''[4][145-151]'(CC1) ,'[5][151-157](CC2)' 
        res = res_cat2idx[unit][0]
        for task in tasks[unit]:
            rtn_profile[res][task] = [-1] + [0] * (task_duration[task] - 1) + [1]
            if stage == 4:
                rtn_profile[res][task] = [-1] + [0] * (task_cleanup_duration[task] - 1) + [1]     

# heat consumption and generation for the first three stages
for heat_idx in range(0, num_heats):
    # process task generate intermediate heat H_A_S (after stage)
    for task_cat, res_cat in [('EAF', 'H_A_S1'), ('AOD', 'H_A_S2'), ('LF', 'H_A_S3')]:
        task = tasks[task_cat][heat_idx]
        resource = res_cat2idx[res_cat][heat_idx]
        rtn_profile[resource][task] = [0] * task_duration[task] + [1]
        
    # process task consume intermediate heat H_B_S (before stage)
    for task_cat, res_cat in [('AOD', 'H_B_S2'), ('LF', 'H_B_S3')]:
        task = tasks[task_cat][heat_idx]
        resource = res_cat2idx[res_cat][heat_idx]
        rtn_profile[resource][task] = [-1] + [0] * task_duration[task]
        
    # transfer task transports heat
    for task_cat, res_cat in [('TR_S1', ['H_A_S1', 'H_B_S2']),('TR_S2', ['H_A_S2', 'H_B_S3']),('TR_S3', ['H_A_S3', 'H_B_S4'])]:
        task = tasks[task_cat][heat_idx]
        resource1 = res_cat2idx[res_cat[0]][heat_idx]
        rtn_profile[resource1][task] = [-1] + [0] * task_duration[task]
        resource2 =res_cat2idx[res_cat[1]][heat_idx]
        rtn_profile[resource2][task] = [0] * task_duration[task] + [1]

# group-heat consumption and generation
heat_consume_time_in_group = dict()
heat_generate_time_in_group = dict()

for unit in (stage2units)['4']:
    heat_consume_time_in_group[unit] = dict()
    heat_generate_time_in_group[unit] = dict()
    
    for group, heats in group2heats.items():
        task = tasks[unit][int(group)-1]
        duration = 0
        for heat in heats:
            consume_time = int(math.floor(duration/rtn_t0))
            resource = res_cat2idx['H_B_S4'][heat - 1]
            rtn_profile[resource][task] = [0] * (task_duration[task] + 1)
            rtn_profile[resource][task][consume_time] = -1
            duration += (equip2process_time)[unit][str(heat)]
            generate_time = int(math.ceil(duration/rtn_t0))
            resource = res_cat2idx['H_A_S4'][heat - 1]
            rtn_profile[resource][task] = [0] * (task_duration[task] + 1)
            rtn_profile[resource][task][generate_time] = 1
            heat_consume_time_in_group[unit][heat] = consume_time
            heat_generate_time_in_group[unit][heat] = generate_time

# energy usage
for stage, units in stage2units.items():
    stage = int(stage)
    for unit in units.keys():
        norm_mw = float(equip2mw[unit])
        for task in tasks[unit]:
            total_energy = 0
            if stage < 4:
                heat = task - tasks[unit][0] + 1
                total_energy = norm_mw * equip2process_time[unit][str(heat)] / 60
            elif stage == 4:
                group = task - tasks[unit][0] + 1
                for heat in group2heats[str(group)]:
                    total_energy += norm_mw * equip2process_time[unit][str(heat)] / 60
            profile = [norm_mw * rtn_t0 / 60] * (task_duration[task] - 1)
            profile = profile + [total_energy - sum(profile)] + [0]
            rtn_profile[res_cat2idx['EN'][0]][task] = profile
            
rtn_profile, heat_consume_time_in_group, heat_generate_time_in_group

time = list()

for x in range(0,int(num_t)+1):
    time.append(x)

res_list = [res for cat, cat_res in res_cat2idx.items() for res in cat_res]
task_list=[task for cat, cat_task in tasks.items() for task in cat_task]


steel=gp.Model('steel RTN')

Resources=steel.addVars(res_list,time,vtype=GRB.INTEGER,name="Resources")
Tasks=steel.addVars(task_list,time,vtype= GRB.BINARY,name="Tasks")   

res_list1 = [res for cat, cat_res in res_cat2idx.items() if cat != 'EN' for res in cat_res]

Resourcebalance = {}
for res in res_list1:
    for t in time:
        sumexpression = gp.LinExpr(0)
        for task in task_list:
            if task not in rtn_profile[res]:
                continue
            duration =  len(rtn_profile[res][task]) - 1
            for theta in range(0, min(duration, t) + 1):
                sumexpression.add(rtn_profile[res][task][theta]* Tasks[task,t-theta] )

                Resourcebalance[res,t] = steel.addConstr(Resources[res,t] ==
                                                 Resources[res,time[time.index(t)-1]] + sumexpression,
                                                 name="Resourcebalane[%s,%d]"%(res,t)) 

res = res_cat2idx['EN'][0]

Energyusage = {}
for ti in range(int(num_t)):
    sumexpression = gp.LinExpr(0)
    for task_cat, task_list1 in tasks.items():
        if 'TR' in task_cat:  # transportation has no energy consumption
                    continue
        for task in task_list1:
            duration = task_duration[task]
            for theta in range(0, min(duration, ti) + 1):
                sumexpression.add(rtn_profile[res][task][theta]* Tasks[task,ti-theta] )

                Energyusage[res,ti] = steel.addConstr(Resources[res,ti] ==sumexpression,name="Energyusage[%s,%d]"%(res,ti)) 

heat2tasks = [task for task_cat, task_list2 in tasks.items()
               if 'CC' not in task_cat for task in task_list2]

Taskexecution=steel.addConstrs((gp.quicksum(Tasks[task,t] for t in time)==1 for task in heat2tasks),name="Taskexecution")  

group2tasks = dict()
for group in range(1, num_groups + 1):
    group2tasks[group] = [tasks[caster][group - 1] for caster in stage2units['4'].keys()]

Taskexecution1=steel.addConstrs((gp.quicksum(Tasks[task,t] for t in time for task in group2tasks) ==1 for group in range(1, num_groups + 1)),name="Taskexecution1") 

for res_cat, resources in res_cat2idx.items():
        if 'H_A_' not in res_cat:
            continue
        print(resources)

resourcesafterprocessingtask= list(range(6,30)) + list(range(30,54)) + list(range(78,102)) + list(range(126,150))

Transfertime=steel.addConstrs((((Resources[res,t] for res in resourcesafterprocessingtask) == 0) for t in time),name ="Transfertime")

x={}
for res_cat, resources in res_cat2idx.items():
    if 'H_B_' not in res_cat:
            continue
    max_wait_time = trans_time_max['TR_S%d' % (int(res_cat[-1]) - 1)]
    min_tran_time = trans_time['TR_S%d' % (int(res_cat[-1]) - 1)]
   
    for res in resources:   # each heat a constraint
        x[res] = (math.ceil((max_wait_time-min_tran_time)/rtn_t0))

Transfertime1= steel.addConstrs((gp.quicksum(Resources[res,t] for t in time )==x[res] for res in x.keys()),name="Transfertime1")

res_list3 = [res for cat, cat_res in res_cat2idx.items() if cat == 'H_B_S4' for res in cat_res]

x=[]
x.append(time[95])

Endresources=steel.addConstrs((gp.quicksum(Resources[res,t] for t in x)==1 for res in res_list3),name="Endresources") 

reslist2=[]
reslist2.append(res_cat2idx['EN'][0])

obj=gp.quicksum(price_energy[t-1] for t in time)*gp.quicksum(Resources[res,t] for res in reslist2 for t in time)

steel.setObjective(obj,GRB.MINIMIZE)

steel.optimize()

My Model is showing this error. I tried many times using lp.write or IIS , but I am stuck like what this is stating, I have decoded 5 times but still I am here.

Please can anyone throw some light ,like I have tried to check what is the issue but I am not able to resolve it.