I have this Ender 3 V2 Neo that’s been doing a really good job until now. I don’t print a lot, but I got it used so it’s probably got some hours on it. It just started doing this: It stops mid-print and gives an alarm that says bed and nozzle temperature is either too high sometimes or too low sometimes. It won’t do anything from there and I have to turn it off, and luckily it gives the option to resume when I turn it back on. It’s getting more frequent, to the point I’ll have to finish this print on my other machine. I know a little bit about hotends and components, from fiddling with my Prusa, but I haven’t had to touch anything on this one yet, so I don’t know its particular ins and outs.
Side note: when it happened just now and I resumed it, the Z was off quite a bit. High enough to have no adhesion to the existing material. The last 3 or 4 times, it resumed at exactly the right Z and continued printing well.