MTN DOES NOT CARE ABOUT CUSTOMERS! ONLY MY MONEY

I took out a new contract in December and had to return the phone within a month. I only received my new phone in April. During this frustrating process of getting a new phone I was promised that my account would be credited for the period during which I did not have the phone as my account was still being debited during this period. Now that I have the phone MTN still keeps on debiting my account and there is no mention made of the credit. I want this resolved immediately. I have been acting in good faith by continuing to pay my account but it seems like I will also have to start negating my responsibility in maintaining my agreement responsibilities. If this is not resolved within the week I will approach my legal representatives and the Consumer Protector for relief.