Bad Customer Service

I had a contract with MTN. I decided not to take out another contract once my contract expired. MTN kept on saying that I had arrears payments outstanding the whole time. When I asked them via mail to explain in detail what the outstanding payments are and how come there is still outstanding payments, they are unable to explain to me why and kept on deducting funds from my account. Even though my contract expired. I would def not take a contract again with MTN and would not recommend doing it.