Nashua Mobile Migration disaster

I am ex-Nashua Mobile, transferred to Vodacom with the buyout of the clients. In December I received a invoice from Nashua Mobile, so I paid so that the account was not suspended. After incurring bank charges for the payment and notification, I received an SMS from Vodacom to state I am in arrears, the amount is for the money paid in December to Nashua Mobile. The supervisor refused to transfer me to the department manger and I had to threaten her. I requested the manger please make comments on my profile to indicate that I do not want to be contacted for any reason by Vodacom and she refused to help. Apparently Vodacom cannot even with proof of payment, speak to Nashua Mobile on behalf of their new clients to assist with payment that were incorrectly paid. Apparently the only thing that Vodacom can do is to give me another number and request Nashua refund my account and then I have to pay Vodacom again and incur additional bank charges. This is beyond unacceptable service.