REFUSAL TO GIVE ME A STATEMENT

I went into arrears with my Mr Price account this year. I was handed over to ACS and subsequently set up a debit order of R250 a month. I haven't checked previously but yesterday when I checked online I saw that my balance as at 07/2018 was R434.00, my account was still debited in August/September/October. I requested a statement from Mr Price, however was told that they could not send to me as I was handed over and I must contact ACS. When I called them the lady insisted I still had a final d/o of R119 to pay. Her excuse was that they charge interest in arrears which didnt make sense to me and when I called her out on this and requested a statement she put me in hold and when she came back on the line - tells me (as if she is doing me a big favor) that they have waived the final amount and that my account is now free, however I can call back next month for a paid up letter as it was on d/o. When I asked for a statement again, she became flustered and tells me she cant give me a statement as she has closed my account when she wrote off the final payment. when I insisted I require a statement to see my payments she then tells me that my account has been closed by the store and she cannot give me a statement.When I kept insisting I require a statement she said she will put me through to her manager - however I'm not sure what she did because there was only dead air. I waited for a few minutes and cut the call as I was at work. This behavior is ridiculous and leads me to believe that something untoward has occurred.