Airtel — International Roaming for USA do not work at all mobile number [protected]

I had paid for international roaming to Airtel for my phone no as mentioned above On November 2 nd 2020 but I don't received any services I mean outgoing and incoming facilities from Airtel or its collobrating company AT&T in the USA till date. I had made so many complaints but my issue doesn't Resolve till now. I had send my representative Three times on every day since I paid to your Ahmedabad office With details as mentioned here but I can’t get any satisfactory answer from this office. I have not such expectations from your well known company in India. I would request to Full refund my recharge Amount res.3997 because I am not satisfied with your services.