Magic Chef freezer not freezing.

Freezer decided to stop freezing. Unplugged unit overnight to defrost. Plugged unit back in the next day and the compressor started but shut off in a few minutes. dug into unit to test thermostat and no clicking noise to be heard. Plugged back in and unit ran fine for a week. unplugged to reassemble the unit 9thermostat housing back on frame) and plugged back in and unit does not freeze. Any suggestions. Thermostat does not click and both red and green lights are on. Compressor is warm to the touch. Should I focus on the TStat or look elsewhere. Any suggestion is appreciated.

Bypassed the thermostat today and dropped 8 degrees t0 46 degrees… That’s as low as she went then started to get warm again. Tapped on the box by the tank (I am clueless as to what it is) and it buzzed for a few seconds then quit.