Account

Hi, I had an outstanding amount on my acount, I went and settle it assuming they wil stop my debit order becuase my account show zero. But yet they went and debited my account. I phoned the account department and ask them why they have debited my account, the responce was yet again that they have to munually stop it and it did not happen, then I have asked could they refund it and the response was that I need to go into the bank and reverse the monies, so I havesaid but you have debited please refund. Then they have said it will take 3 months to refund the monies. They always receive the my debit order in time but not happy when they made there problem mine. This is my 3rd study I have taken on but now I see how it works! Why?????