Account debited twice - I am not your customer!!!

I had a previous complaint regarding an invoice and debit order that you sent me for R 216 for July even though my contract was cancelled 28/07/2015. I finally, after how many weeks, received feedback from Patience Mtshali on 31 August. She said that the R 216 is correct because my account expired 15/07/2015 and the R 216 is for calls and data from 16/07/2015 - 27/07/2015 - WHAT?? when I phoned and emailed your call centre in June 2015 and enquired when my contact expiration date was they advised 28/07/2015?? Why didn't your agents inform me that the expiration date was 15/07/2015?? because I would have chosen the cancellation date to be the same?? This is your fault - I WANT MY MONEY BACK!<br> Then now I receive another invoice for September?? WHAT? If you do not return the money you have already debited from my account and if you debit this invoice for September I will lay a formal complaint against Autopage for ********ly putting through debit orders on my account.