Reliance Jio Infocomm — Incompetent to provide service and not refunding the amount paid

Address:

top floor, H No. 91, Mayur Vihar Pocket -1, Delhi -110092

I connected with Jio to provide internet service in my house, they took 6 months of payment in advance for the internet connection, but were incompetent to give any internet wifi connection. I'm trying very hard to cancel my order with them and for refund. but since 3 days i got more than 30 messages for re-installment / re -appointment for installment.
I have never asked for re appointment and they itself accept that they cant provide me internet services, but till now i haven't received any email/mail for cancellation.

calling their customer support, but till now they have not cancelled my order, now this is the 4th day and I'm unable to do work from home neither they are refunding the money nor cancelling the order.

they give me 15 minutes to pay for the whole 6 months in Advance and there is no contact or mail or messages for cancellation and refund.