EFT Payment to Nashua Mobile - Account sold to MTN

I've been a Nashua Mobile client for a long time and have the same number since they bought it from Plessey Cellular. Received notification that account was sold to MTN. The transition to MTN was nightmarish. The billing dates differ to Nashua Mobile. Experienced mix up with payment and line was suspended. Finally sorted things with MTN. On the 25th May I paid Nashua Mobile instead of MTN, as I forgot to delete them from the beneficiary list. On 02 June I received notification that my account was overdue and ignored it, as I knew I made payment. On the 08 June I was informed that my outgoing facility was suspended. What an inconvenience. I called MTN after checking payments and realised what happened. I requested that they re-instate the line as payment will be made. Told them that I am trying to get hold of Nashua to have funds reversed. I called Absa and it will cost R160 and no guarantee for reversal of funds. I also asked MTN for contact details for Nashua as I need to get the money returned. All numbers I have tried says non existent. Also checked with Nedbank and Nashua account is still open otherwise my money would have been returned. Would appreciate some assistance please