Bank charges, taking insurance without my consent and making changes on my contract.

I had a bad experience with Mtn making transactions in to my bank account costing me bank charges even after paying them cash in their store. Making changes on my cell phone contract without my consent. They took out the insurance for my contract and made desicions without me. Went to the Northgate branch to tackle the issues but was failed to get help as I was told I need to contact the call center were by I never got to conclude my case because nothing much was done for me. I feel Mtn is a company that keeps reaping people of at every chance they get. This is the route I decided to get attention as no one takes responsibility for the this issues I have raised. My name is Vusimuzi Mkhwa****