Frigidaire full refrigerator (PLRU1778ESO) not getting cold at all, everything runs fine?

The frige will not get cold at all. It runs, lights work, compressor turns off (and it get's warm), turns off for the defrost cycle and on again, fan works, drain isn't clogged. Everything looks great except it doesn't get cold. There will be some cool air coming in but never cold enough. It wasn't used for several months, plugged in and appeared to be doing fine but in the morning it was almost room temp.