Avoid Airtel store at connaught place -BEWARE

hello delhites, i want to share horrific experiences with connaught place airtel store, where i paid for WIFI service, yet my WIFI was not installed, and upon requesting for the reciept, i am not getting the reciept too. Airtel has the worst service, you cannot reach out to anyone, basically i got robbed here. I am in the loop trying to reach out to their customer care since 3 days, but no use. I have mailed their email ids, i have ss of texts with their employee, where she is of no use. Guys what should i do please help. I paid for airtel fibre 6 months upfront, amount of approx 2.3k, please tell me what to do.