BAD service all round

I have placed an order which was accepted and paid for on the 29th of November. I phoned Groupon on the 9th of December to track the delivery. They gave me the courier company details (Churchills International Express) and according to the system the order has been dispatched on the 2nd of December. I phoned the courier company and struggled to get through each time - eventually got the customer services manager to whom I explained the importance of them delivering the package on time. She said they'll get back to me. I had to follow up yesterday and today and no one is able to tell me where my package is. It is now too late already. I feel that Groupon remains ultimately responsible for choosing the courier (which is the worst service I've ever experienced) and now the delayed/lost package. I tried to phone Groupon now to speak to a superior but the call centre agent put the phone down after I held on for more than 10 minutes to speak to someone. Please contact me to sort this out urgently.