RCS loan

RCS is not trustworthy. I have about 3 accounts with them, the other 2 account are not giving me issues but the loan account is the problem. RCS is debiting from my account, they stopped debiting after I paid a lump sum of about 96%of the remaining balance. 3 months down the line I got a call saying that my account is in arrears, I asked how is that possible because they are debiting, I asked them if the debit is still active and they said yes, I asked them why they didn't debit and they said they will do investigation on that and in the meantime I needed to pay R550 and I paid it. I never got a feedback call to tell the output of their investigation but instead, I got a call from their attorneys saying that my account was handed over, I explained to the attorney the situation and they told me to call RCS, I did call them and I even requested a recorded call of 2nd and 3rd April 2020 and they said they will send it, up to now I haven't get anything from them but I keep getting calls and now I am told that I am in a process of being black listed. How is this even possible? This is not a professional way of dealing with customers and they don't stick to their words