Paid up account......

I have paid up this account in the middle of March with the balance from a settlement letter. I even called to query after receiving the settlement letter that all is in order, and i could make payment, confirming the amount. I then paid up this account and called in again to confirm payment was received and requested that the account be closed and im issued with a paid up letter. however at the end of March my account was still debited (for a small amount) which is not the point really.....Highly disappointed in their poor service.