Payment not reflecting!!

Since last week I've been struggeling with Mtn to sort out my Billing Account. Last week I've been forwarding my proof of payment to them. On Saturday I received an sms stating that my account is still in arrears and my lines will be suspended, but according to my payments I am up to date with my account. Yesterday someone from the call centre phoned me and I asked again about a proof of payment. I told the agent that I even took a proof of payment to my nearest Mtn store, and was told my phone lines should be active again by 8 this morning, and has not been activated again! I received a call from a agent about an hour ago and was told that my lines will be active in an hours time but still nothing. I just want my damn lines reactivated cause I paid that was due and my account is up to date. Last week I forwarded my proof of payment 3 times to a email they gave me but yesterday they still haven't received my mail and don't know how is that possible. Calling the call centre is useless with no answer and no help. When I'm contacted by their agents it sound if they have no idea about what's going on have no idea how to help me!! Getting very tired and sick of this!!!