Delivery Delay more than a month and to say sorry

I ordered and paid for Cars bedding for my son 23 November 2015 and was advised instead of 5 working days my order would be delivered in 15 working days. Well i thought it was enough time as my sons birthday was on 21 Dec 2015. After following up i received an email advising me they have not found a solution to my case. WHAT??? i never even knew what the problem was. Today i get an email advising me that they are out of stock and will refund me. Well i want my refund today and it MUST reflect in my account by Friday. I tried calling their call center and they apparently are not taking any calls. I demand that a manager contact me and explain how this has happened i bought 2 sets of bedding the same day the special started. I would rather pay full price then buying from you *******.