Airtel — Airtel prepaid sim not working

Hi, I recently travelled to India in Aug 2022 and changed my SIM from Vodafone postpaid to Airtel Prepaid. The port was successful on Aug 28, 2022. I travelled back to Canada in Sep 3rd 2022 and used airtel SIM for 3 months. Suddenly in Nov end, SIM dint work. The balance amount was INR 40. Am not able to recharge / receive any OTP from India. Attached are the proof.

26.08.2022 - +91-[protected] - ported successfully from Vodafone postpaid to Airtel Prepaid

When I asked my fatherin law to visit Gowrivakkam airtel store, cennai, He was told there is no such airtel number in their record. How can I successfully use number for 3 months and suddenly am not Airtel's customer is I dont understand