Airtel — unethical behavior and cheating

I am a subscriber of airtel, 2015 i have added a child sim with my main sim which is rarely used. From the last one and a half year, it is not all used. I am trying to remove this from my main bill plan, every time the concern customer care team assure me to do that but when i do call back again i use to listen to only one sentence that "your request not processed but do not worry i will do it sir and you can sit back without any tension"

Every month i am paying my bill for my main sim almost without using it then also they are not separating my child sim from it.

I am fed up dealing with all these people. Please kindly help.

Thank you