MTN Overcharging customers and not resolving the problem

Dear MTN

Your call centre is very unhelpful You don't call back your, this is an absolute nightmare. You keep sending me statements yet I have trying to get a hold of you to inform you that my sim card was ****** . Who do you think is going to pay for that account

The way your system is so outdated you can't even see if calls have been made from that Simcard or not ... All you do is to deduct money from our accounts for WHAT??????

I will never ever use your services again ... Please don't upgrade the contract after it ends