ARREARS INTEREST CHARGED INCORRECTLY

I have a personal loan and it is kept up to date. On 24 December my debit order went off as well as arrears interest of R2.37<br> Luckily for me this info is displayed on my Internet banking from FNB. I phoned Direct Axys and the agent told me that it is a system error and it sometimes happens. He told me the lady that will correct it is not there but it will be done. This was in January. I then also emailed in February with automated response email back to say an agent will contact me. Nothing happened. I phoned again in March and the agent told me that he can see it is correct on the system. It is however not correct on FNB internet banking. Mention was also made that it is a small amount and somehow anything below R100 will be written off. I do not care about that. I want to see that the arrears interest is reversed. My account is not in arrears, in fact i always pay in extra about a R10 at the beginning of a new loan because this arrears interest has happened before. <br> I want you to fix your system and reverse my arrears amount of R2.37