Paid service suspended!?

I have paid my account on time and have been surprised this morning with a suspended account! I have been holding on for more than half an hour to speak to a consultant. I sent 3x mails with the proof of payment but no response or assistance!<br> Now I have a bad track record because someone in MTN accounts depatment is not doing their administration. They are quick to suspend you, but not so quick to correct their own mistakes and provide proper service!