Temporary Loan

I was owing FNB (Temporary Loan) Amount , they handed my account to Groenewald Lubbe Attorneys, I then payed half of the amount at FNB Atm as deposit to the Attorneys Account using their account number then it was deducted from the amount I was owing and then I decided to pay another amount which is R330 on the 1st of December 2020 as a bank transfer from my NEDBANK account and I still have screenshots (proof) and it also shows at my bank statement and after some time they told me that I’m owing that amount I should pay and was very shocked and surprised to hear that cause I know very well that I transferred the amount straight to their account , then later on on the 9th of February 2021 I payed the remaining amount I was owing which is R300 but still they insisted that I didn’t pay the amount and they even sent a message today that I’ve been OWING FOR TOO LONG and they will take legal action how come cause I did pay them . I’ve been sending them E-mails and proves and even calling them but still there’s no correction made and any help I get . They are not helping me at all . There’s no amount I’m gonna ya Ke out from my pocket and pay them anymore cause I’m not owing them anything . All they should do is to fix this ASAP and trace the funds I sent to their account since last year.