Superbalist doesnt return my item or refund me... is this then considered theft?

I logged a return more than two weeks ago. They collected the item and said it wasnt in a condition to return. Which is fine. But now they haven't returned the item or issued my money back. They said they were going to return 48hrs later. It is now two weeks. I have called a number of times and emailed at least thrice. This is completely unacceptable