Loan Account from HELL

Good day

I have a problem with FNB personal Load, based on the account statement dated the 21 April 2018, my account balance was R108 954.94 and on the 24 April 2018 I paid R30 000 directly into the loan account and the new loan balance now R78 954.94 . On the 7 May 2018 an amount of R4013.01 was debited on my personal account as the loan payment again, but what really I dont understand is that interests were charged and my account balance still remained at R78 188.00 after the R4013.01 payment, dispite my credit balance of R9 550.01.

I requested my private banker to assist me to resolve this matter and according to me she has done her best to resolve it but its just the incompetency of the personal loan staff that annoys me. On the 08 June 2018 I got an sms notification that R24 463.00 (Which I believed came from previous payment when the account was reconciled and the balance was now R56 414.00.

Today I got another sms notification saying R20 863.00 has been paid to this loan account buy surprisingly the account balance is now R91 138.00, the bank has something going on in this account. I can not get answers for such a jump wheres my payment are upto date, the account balance just keeps on going higher and higher despite payments