Account error

My debit order went of before my salary came in then my account went in to error ,when i got my salary they took the money that was in error plus an aditional amount witch they say my account was in error but it was not , they keep on taking small amouts out of my account where it does not show any trace where the money went to , i am highly dissapointed in the bank. And the service's from the consultants is like they really dont want to help the customer .