Summit ff1415ss; freezer cools bottom is not cooling
I bought a summit ff1415ss a while a go, it has been working fine for a couple years but in the past several weeks I've been having problems with the bottom part. The freezer is cooling and actually there is frost forming which might be a sign of a seal leak, i think this is a frost free fridge.
The bottom part is actually not cooling, I have checked the seal and it seems it is not making contact in several parts, I try to patch it to see if that might be the problem, it was fine for a couple days but then it went back to not cooling the bottom and frosting the freezer. I also noticed in the bottom part there is water and water drops on the roof.
I read somewhere that if you have these problems you should turn the fridge off and let it defrost for several hours(freezer door open), then turn it on, I did this and it worked fine, both(freezer and bottom) were cooling as they should, but after a couple days the freezer started forming frost and the bottom doesnt cool at all.
I was looking at replacing the seals and start there, but I tried to find summit parts specially the seal and cant seem to find these, any ideas on where to find these seals, are these like standard?