Bank loan

We have a bad experience with fnb last week when we checked the loan balance was R8250 and today when we make a payment it was on R9246.00 this company sucks big time how can a loan increase while we are not even skipping any payment.instead it keep on increasing. I wouldn't recommend anyone to take their loan they **** people big time.thats why they keep on renovating bank city its because of the ridiculous charges. I really hate this bank seriously. They don't even have walk in branches u keep on talking to a useless consultant that won't give u even a straight answer.they can't even send u the statement that's how useless this bank is.how come interest is soo much on black people only for only a week interest is very high but we making payment every after 2 weeks.