Close a MTN Contract.

I have been a customer for years but fell behind with my contract payment due to financial issues. Received a Final Notice of Early Cancellation - including a cancellation charge which were paid with pleasure. Requested confirmation, number suddenly active, requested final figures for proper cancellation, paid it, less a credit that I had. Several calls/emails back and forth. 19 November. Now still have a credit along with being charged. Have emailed all relavent mtn departments the last time today. I just want the contract SHUT PERMANTLY and in a fair way. Praying this will be finalised once and for all.