9 Days and Refund still not paid back

I have asked for a settlement letter so that I can pay off my account and close it. Letter was send and I paid the amount they stated in the letter. After about 2 days I phone in again and asked for them to close my account, they said that I have over paid them and that they need to refund the money before they can close the account. I asked Lady what they needed and I send them all the Documents on the 10th of June on the 17th when they said that Refunds goes trough I phoned in again about my Refund. Again they had stories that they do not have all the paper work needed to process a refund, I send them the documents again and they said that payment will be done on Friday the 19th. I again phoned in today regarding my refund as nothing is still in my account. He told me there is nothing he can do, They paid my money back this morning, and when I asked for proof of payment they could not provide. He just said I must take his word that its been pain into my account. I have struggled now 9 days the get my Refund back and still nothing has been done.