Truworths installment error

In February 2022 I called truworths customer services to confirm what my installment should be as I had been paying 920 for over a year every month without the amount ever changing yet the account balance was sitting at around 3400 at the time. During the call the operator requested that I hold the line so she can recalculate the installment due as she said it hadn't been recalculated as it should've been months ago. When she got back on the line she told me the amount due is R350 and not 920. I then asked whether it would reflect that way on all the systems or cause a problem later to which she assured me it is that way on the system now that she has recalculated it. I paid the 350 installment as she had said, just to receive messages now from truworths stating that my account is in arrears of +- 1500. My question at hand is, how is it my problem if a consultant told me the amount due is 350 and that is what I paid, my account has never been in arrears and now suddenly when I'm this close to settling the account it suddenly goes into arrears. This is a fault on truworths side and they are responsible for rectifying this matter. As stated all calls are recorded, and I would like my calls retrieved as proof of the conversation between myself and the consultant in February where I was informed of the 350 installment after recalculation was done. I called on Thursday and was promised a call back from a supervisor which I still await as I refuse to pay the arrears for a mess up on truworths side. My calls are recorderp for my own security too.