No response from Game Online

I purchased a Spinning Bike for my wife for Christmas and this arrived just before Christmas which was a great surprise for my wife. However, testing this the bike had very little tension which was disappointing! We called to manufacturer Trojan who were very responsive and came to our home and suggest we return this to Game and purchase a different model. Game's couriers collected this on Saturday 8th Jan. after I carefully repacked everything in the box the bike came in and Game said we would receive a credit shortly, but this has not happened! Contacting Game Online purchases via email and several phone calls, we have been informed that the item receipt has not been confirmed by their online store and even though they tried to contact them while I held on, the phone was just hung-up with no confirmation by their stores department! They said they would find out and get back to me! It is now 26th Jan. and my wife still does not have her Christmas present from me. I cannot get a response when I will be given a credit so I can purchase a bike which we can test before we purchase this time!