Overcharged in my 649 plan

Dear Sir/Ma’am,

I am using Airtel sim 649 plan on my phone. I also have 2 child numbers connected to my parent number 9830522344. I have been highly over charged (about Rs.8000) on my bill.
According to the airtel executives I have been charged for child number’s roaming services. But when I took the plan I was been told that my roaming will be free and the child number’s benefits would same as parent number. They have now disconnected outgoing on all my 3 numbers due to non-payment of bill. I had called customer care several times to confirm about the plan and benefits of child numbers. All the time they have said that child number has all the benefit as parent number.

I request to you kindly look into the matter and ask them to waive off the extra amount charged.

Thanking You.
Regards,
Girdhari Lal Thard