LOAN *******!!!!

FNB loans deduct every month when any money come in to my account the last 4 months they tell me I'm in arrears. Then when I call and they transfer me between consultants they 'found' the problem. In April I asked that both loans be deducted month end!!!!the one still hasn't been changed!!!!They deducted one of my loans twice last month I struggled almost 3days to get that 2nd payment back. Today after I got paid they deducted my 2 loans and send me another message saying I'm in arrears by over R1000!!! How????? They take the money as soon as it is deposited!!!!!