Bad debt

Hello Peter, I bought clothes on acc at foshini in August 2017,lost my job so I couldn't pay... They handed me over to Dmc, which I agreed to pay R1000 a month, the lady I spoke to in August 2020 said if I'm willing to pay R1000 a month then I will be discounted R8500, I agreed and began to pay.... I reversed some payments but as per my bank statement, I've paid more than R5000 but it says I still owe R7500.. I want to send them my bank statements bcus it gives details of my deductions ND how much I've reversed but they hv refused, they said they only see 3 payments on my dmc statement so they don't want my bank statement. Please help because I will like to settle this debt. NB: I contacted Dmc via whatsapp few months ago nd they told me my acc has been handed over to blake and associates so I do not know if some deductions were made from blake but Dmc did the monthly deductions