Europa/Bedmart Doesn't Honor Warranties

We have tried for the last 3 years to get Bed mart and IBC Europa to honor the 10 year warranty on this matress. After the first year of having the matress we have a 3" depression on each side, where we sleep. We followed all instructions about standing up the matress for a couple of days and such, as we were told to do this by Bedmart. then we find out they are supposed to replace the matress if the impressions are over 3/4 of an inch deep, ours are over 3"... Bedmart won't honor because the actual store we purchased from is closed down. Bedmart didn't put our information on a database, so no warranty for us. I'm ready to just give the matress back with with something extra, right through a window.