Don't buy a defy fridge from hifi

I have never had such a bad experience in my life with purchasing a big appliance. I bought a Defy fridge 6months ago from Hifi, the fridge was giving problems. I reported it and they replaced it. I received the new fridge and this one to is giving problems, it has a dent at the back... (suppose to be brand new) I reported it to the store and the store emailed it to Defy, but they never responded. I just wanted them to know about the dent. The fridge makes funny noises, it freezes again and again. And it is suppose to be frost free...... What must I do..... Defy you suck..... Hifi I am unhappy.