Airtel — Prepaid SIM Invalid

I've been using my Airtel number for the last two years. I took it personally by visiting an Airtel store in Hyderabad, Telangana circle. I submitted all required documents, id proof with etc. It was taken as a postpaid connection, after two months o[censored]sage I converted it into prepaid at the store itself. It was verified and I could use it.

Now after two years, I'm getting message that my documents are invalid and SIM has been blocked or not provisioned.

I visited a nearby Airtel store, but they say they are unable to find any details and I need to visit the store from where I first took the SIM. I left Hyderabad 2 years ago and for this I am unable go to Hyderabad. It's very disappointing to have this experience.