still waiting for Refund

I booked for 4 chalets for 20-22 Nov and paid on 29 September. On the 4th Nov I cancelled 2 units ( cancellation ref number *** and ***) and submitted cancellation form with copy of ID. I was told it would take 10 working days for refund to reflect in my account. Eventually checked in on the 20th and still no refund for 2 cancelled units. I'm the one who keeps callibg and emailing to find out what the delay is. Got told on the 25th Nov that my documents that I sent on the 4th Nov only reached finance on the 23rd Nov and that I would wait 10 working days. I phoned again 14th Dec to be told refund not processed and no clear indication when it would be paid. I have been more than patient. I want my refund with interest for all the days it has sat in your bank account