Airtel — incoming call not working

Dear service provider

My number [protected] - bsnl to airtel mnp on 02.03.2018.

Activated on 09.03.2018,

09.03.2018 to till date and time incoming calls not activated.

I speak to 121 customer care in past 20 days above, but not solve my problem.

2 times i change my sim as per your 121 engineer advise but problem not solved.

2 times i am conduct in local airtel store in chennai and coimbatore. But not solve my problem..

What can i do.?

Regards

Vijay kumar e