Airtel — it is showing no service

I’m using airtel 4g which is showing no service for the past 3 hours. No issue is handset where i checked with other sim too and it is working fine.. Network selection is disabled and i tried to customer care 121, 198 where i couldn’t talk to any representative.. It’s very urgent pls do check and let me know why it is showing as no service. Please check this as soon as possible