Upright Frigidaire Freezer not freezing

Brand: Frigidaire
Model Number: FFFU16F2VW, purchased in Jan 2022. (Located in garage)
Main Symptom: Not Cooling at all

A week ago, green light started flashing & beeping noise (indicating not at proper temp). Noticed the freezer was cool, but not cold. Checked it the following morning, same thing. Unplugged freezer to “reset” it (for 10 mins), same issue the next morning. Went on vacation for four days, came home and it wasn’t cool at all (obviously removed everything before we left). There’s no display to check the “codes”. I’ve taken it apart, no burn spots or anything on the main board, looks fine to me. Confirmed that the evaporator motor is working and spins freely. I have no idea what the resistance specs should be on the temp sensors/evap heater, everything online shows different readings, but here’s the readings. Readings taken at 80 degrees F, ambient air temp.
Defrost air duct temp sensor: 1,795 ohms
Thermistor: 1,828 ohms
Evaporator heater: 68.9 ohms

When I unplugged it yesterday morning and took it apart, there was a small piece of ice buildup on a small line leaving the evaporator (can’t see where the line runs), no idea if the evaporator was completely frozen since it sat for a week. The freezer is not dirty at all, no dust or cobwebs behind or underneath it, it’s basically in brand new condition besides the fact its four years old. It’s located in my garage which does get hot during this time of the year in Georgia, but this is supposedly a garage ready freezer, part of the reason I bought this unit. The door seal is good & seals just fine. This is the first issue we’ve had out of this freezer, I’d expect it to last longer than four years.

Any thoughts??

Thanks for reading such a long post!