MTN pay back the money

Please can you assist me with getting my money back, I overpaid my MTN account that was handed over to MBD attorneys. On the 5th of September 2018 I paid R3 315.11 as a settlement amount for my MTN account that is with MBD, then on the 20th September 2018 I paid an extra R1000. I still haven’t received my money back from MTN or MBD attorneys and have send all documents. They said I will only receive R700.00 as the account is over paid by R700.00 and not a R1000.00 I have requested a refund from MTN but since my account was handed to MBD they referred me to them when I call MBD they say MTN hasn’t responded and they can’t tell me if or when I’ll receive my money.

I just want my money and not all this stories that i'm currently receiving, surely by now MTN can track/locate and refund me.