Airtel — no response for my concern - 4g connection problem for past 9 days

Address:

Hyderabad, Andhra Pradesh, 500084

I have a prepaid sim that i requested to convert to postpaid. Got the new sim at my corporate office, visited airtel office and submitted all proofs and completed formalities on 18th november evening.
Till date, i have raised the concern multiple times that my 4g is not working using new postpaid sim but there's no resolution from any customer care person of airtel. I received multiple calls from customer care but everytime i need to repeat the problem and reiterate with more clarity.
Complaint no. S 81327470, [protected]. More to the pain, my mobile still says, it is prepaid when i try to connect to customer care. I have to use other mobile to talk to customer care.
Airtel accepted that there is a technical glitch and it will be solved in 1 day, 3 days etc but no solution till date.
My problem is still not solved and i do not have 4g connection for my sim. I am facing lot of challenges at work and also to commute to home at late night as i do not have chance to book a cab.
I am very disturbed mentally due to this discomfort by airtel. Request immediate action.