Was close to this earlier this year. Went into the freezer for a pizza and it was thawed. GFCI had tripped for some reason! Glad all the meat was still frozen!
I had a close call this past summer when my kids messed with the controls on the side of my deep freezer. The meat inside was still solid but the freezer was turned way up and it was well on its way to thawing out.
https://www.amazon.com/gp/product/B07B9QF64N/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
I duct taped over the control knob and bought one of these alarms with 2 sensors. Tested it out and the alarm is fairly loud and stays on until you shut it off. Pretty cheap insurance for 2 freezers.