How difficult is it to settle an account?!

Nashua Mobile transferred all there cell C contracts to Allpage the Customer information was not transferred correctly. My cellphone account was not automatically paid from my bank-account without notice. After my phone was cut off i called the Allpage callcentre when a lady explained this to me and mentioned that I need to pay R1900 to clear my account. I asked her to send me the invoice and banking details. After receiving the invoice I noticed that there were two cell phone numbers charged to my account only one of which belonged to me. I immediately send her an email asking to correct the invoice for my phone number and contract alone. (18 March 2015). After received no feedback I went to see a local branch directly. I was explained that a query had to be raised this was logged 24 March 2015 and should have taken a max of 3 days. I did not get any feedback and 4 April and informed nothing has yet been done since they needed additional. I provided the info (4 April). I was in contact via email with replies that they were working on it 7 April but it was not finalised by that afternoon. It was escalated and to be sorted within 24working hours. I am again waiting with no response