Airtel - Fraud Calls from my Airtel Mobile Number Security Breach

I have been a loyal customer of Airtel since more than a decade.
I am facing a problem caused by Airtel. I will explain you the problem and hope an action will be taken on it.

Problem Statement:
I have received a bill for June **** month stating that there are several calls made from my mobile number to multiple countries between *th-June to **th-June.
But the fact is i never made any ISD calls from my mobile. I have none of my friends/relatives/or any one living in the countries like Afghanistan/Russia/Bahrain/Hong Kong/Iraq/Kuwait/Nigeria etc and did not make any calls to any other countries as well. This is the clear case of fraud happening in your system. No-one is willing to resolve the same.

I would like to bring this fraud to your notice because I did not get any satisfactory response from any airtel customer care executives, after talking to them multiple times and also raised the concerns with ***@airtel.com.
I am using this number over * years and never made any ISD calls. Why would i suddenly start making calls to these ISD calls(to above set of countries) that too just within the span of * days?
Is it not alarming ? Please look into this matter and help me resolving this and for the future as well. This is a breach in my security as well.

Airtel did not bother to verify the device number for these calls after telling them multiple times to assuring that these calls did not make from my phone. Again I am reiterating that no-one has made any calls to these countries from my phone. I have already set a strong security pin number so that others can not make any calls without my permission. Also i have never even downloaded any video conferencing apps (zoom/cisco etc) on my mobile so there should not be any case of any calls from any video conferencing app.

Request you to bring this issues to Airtel and help me resolving security issue happened using my mobile number