Pathetic customer service

I had a contract with MTN but they are still debiting my bank account.I have called their call centre ,visited their store and sent an email to their Retentions department but nobody is assisting me. This has been going on for 3 months they have caused great distress with their pathetic customer services. The call centre agents are rude they don't have the correct call ettiquette, all 10 calls made to MTN were useless because I still have not received assistance.This despicable behaviour has to stop I want my money back and the employees have to go through internal training for this horrible customer service