FNB loan debiting long after balance clearance

I had already paid off the loan on FNB and now they debited my account with a balance after their forced January no debit was declined and I deposited into the account. What exactly is the R372.65 for as they just debited it long after the accounts were cleared off..on the stop order date there was no debit all off a sudden my account is debited with a figure higher even to the balance I had?? Please call to explain me there fees..this is plain *********** .