Terrible service

In mid November I purchased a shower screen door online from Builders Warehouse however on delivery it was the wrong product which we sent back with the delivery guys. I have since contacted them twice to query as I have NOT received the correct product YET but to no avail. I am totally disgusted with this service as I have had no feedback from them to date. All contact made was made by me - they have never contacted me and it's more than a month ago. I will not purchase anything from them via their online portal ever again. I want my money back!!!