If the freezer is cooling normally, check the door flap and seals for the refrigerator compartment. If the flap doesn't close, warm air will come in. Same if seals are not sealing.
I read somewhere that you need to defrost these types of unit every 2 months, my 1210 was giving me a lot of trouble after putting fairly hot chicken in it to cool.
No codes, but noticed ice on upper rear freezer plates.
Removing ice did not help, I emptied everything, turned off and dried out top and bottom of all moisture.
Turned back on and put on AC and kevel 9 setting for 12 hours and working great again, O and cleaned contacts of bracket where sensor attaches in fridge and hits door seals with hair dryer to reset memory foam.
Update ..a couple of months later, These units must have some goofy programing on circuit board, when it starts warming up I turn off power for a small amount of time and then back on with temp set to 9, starts cooling again, I have been doing this for awhile and has worked. Then it didn't work, went through everything, no issues ... all systems checked out fine, turned off far a day no go then turned off and ponded on inside of freezer to try to knock something loose in this ammonia setup it uses, turned back on and it got cold again. I had also replaced thermistor, was no different and same ohm reading as old one. It seems like the way this thing cycles on and off is the problem, has anyone had better luck running unit in thermistor bypass mode?