Lewis Delareyville

So about almost a year ago, i bought myself a bed from Lewis Delareyville in the North West. Initially i wanted to buy an affordable bed as i was buying it for my rental apartment, however i met a great consultant who advised that i buy rather a good quality bed with benefits, including a guarantee, i then fell for her advise and went for a medi- spine mattress, also looking at the fact that I have a back problem. Exactly 11 months later, the mattress is starting to sag, and I'm now experiencing discomfort. Considering the fact that the bed is still under warranty, i made the store manager aware of my problem and what he asked of me was to take pictures of the bed aswell as the video while jumping on the bed.. I did that and sent the video, was further told that they will come for an inspection and take it from there, he could not deny the fact that the bed was still in a good condition, however I'm being taken from pillar to post, and to date my matter is not resolved. I'm now paying double the amount i had budgeted for and yet struggling to get my matter resolved...