Impossible to cancel order and get a refund.

I made and paid for an order on the 29th July. I cancelled the order on the 1st August and more times during August. Notwithstanding my cancellation the order was delivered to me on the 18th August. I sent it back. Nothing has happened either about my cancellations or the return of the order. I received an email long ago saying that I was to get my money back - I paid by credit card.