accounts dept frustrating

At the end of 2014, my cell c cellphone contract that i had with nashua mobile was taken over by autopage when nashua mobile liquidated. On the 11/3, I rec'd an email of final notice before judgement from autopage. When I called their accounts dept they advised that my account was in arrears. I had to send them copies of my bank statements to prove that they had put through debit orders on my acct on the 25/2 & 27/2 (reversed by bank due to lack of funds as my debit order date is supposed to be last day of the month as this is when my salary is deposited). They then double debited by acct on the 28/2. I then personally reversed the 1 debit. This would mean that my acct was paid up on the 28/2. I have dealt with both a accounts service consultant (Lynette) and her manager (Jocelynne) to get this resolved. Then on Thursday 12th Feb, I get an sms asking to ensure funds available in my acct. I call the bank and they confirm no debit order going through. On Friday 13th Feb evening, nudebt management (contracted to autopage) debited my acct again. I called bank on sat am and they couldn't reverse. Nudebt can't access my details on their system. autopage still can't rectify. ***!