I've been using the same number (+91 [protected]) for the previous four years, and until November 8, 2021, the Sim card worked well. Even while I was working in Qatar, I received missed calls and everything.
When I returned to India in November 2021, I changed the ID proof of the sim card to my name from my brother's name, and I returned to Qatar on December 13, 2021. Since then, I haven't received any calls on this number, only text messages.
Airtel customer support has been notified about the posted complaint.