MTN owes me money

I had an MTN contract which I paid up . The day that I paid the full amount I was advised that the debit order will be stopped. I was then debited I logged a refund query while at the mtn branch on the 22/01/2026.i still have not received my refund and I am receiving statements which show that I am in credit . No one has even contacted me but when they need the sales then they will call all the time . I do not use the network and when I call 083135 I can never get to a consultant regardless of what option I choose .I wonder how many other clients fund have not been refunded and of that money is gaining them interested