Complaints about my account

I have an account with Game stores. Back in 2017 I bought a fridge with my account, a fixed straight line type. But in a period of 1 year and 9 months, the fridge died. They sent the mechanic to my house for 3 times and he failed to fix it. We were then told to take it back to Game Brits where we bought it since it was still under the guarantee time of 2 years. We took it back and we were given a voucher of 11 000 to spend in the store and we bought another fridge. My problem is I believe they made a mistake of adding on the voucher amount to our then existing balance. I went back to the store to request that they review my account and send me a statement but they never did. This is year 5 and I still pay around R600 a month for a fridge that only cost R11 000 in the beginning. I did have some small purchases with the account but I need help accessing my statement from back when they gave me that voucher. Thank you in advance