Samsung freezer not cooling, fridge is fine.

Hi I have a Samsung fridge model RF22M9581SG/AA. The frezeer is not getting cool at all. I noticed it a week or so ago and I unplugged the unit and plugged it back and it seemed to work again for a couple of more days only to get warm again. Unplugging seems to have no effect now. The temps says it's at -10 but it's not and when I unplug and plug it back, it shows the correct temp which is usually somewhere between 37-60 degrees. It'll gradualy go back to show -10 but it never gets anywhere near that. I've checked all the obvious things. The fans seem to be working. The coils aren't frozing. The compressor seems to be running although it MAY be a little louder than usual at times but I'm not sure if that's in my head or not. Is there anything I'm missing that I can try on my own? What's the next recommended step? Any help would be appreciated.