Airtel — devious practice

Address:

600004

On 9/6/18 airtel started a service glamsham without my request or authorisation and charged rs 35 for it.
On receiving that notification i called the stop request number and cancelled the service.

My question is why airtel did start such service and deducted rs 35 without my request/authorisation?
The charge has to reversed and rs 35 should be credited to my account immediately.

Airtel has again started this devious practice of starting some service without customer knowledge and charging for it.