UNAUTHORISED DEBIT AGAINST BANK ACCOUNT

I have changed from one bank to another. Debit order were in place, Netstar notified, EFT payments made to<br> Netstar for the months of September, October, November and December R149.00 x 4 =R596.00. Cancellation letter done on the 22/12/2014. Contact by Nudebt whereby proof was sent that payments has been made on SEVERAL OCCATIONS. Still getting the sms every month account outstanding. <br> <br> On the 24/3/2015 our old bank account were debited with the amount of R572.40 being the 4 x R149.00 payment already paid by EFT. <br> <br> How many times do I have to sent proof of payment, how many times will I still be contacted re non payment, how am I going to get my refund.<br> <br> This is so frustrating getting nowhere, maybe I should write off the R572.40 and forget about it, in the other hand it is money due to me