(Excuse the wall of text, the first paragraphs are some backstory)
About 2 years ago I bought a refurbished Dell Precision M6800 (a 2014 model), and I started having the sudden reboot and ASF2 Force Off thing regularly after a couple of months. It could sometimes happen with the laptop being untouched, but it usually happened whenever I moved the laptop, didn't matter if it was with a battery or not (mine has a removable battery still), plugged in or not.
One repair shop said they could not do anything about it (they said try reinstalling Windows).
Another one though immediately suspected a broken trace in the motherboard, however they inspected the board carefully and found no broken traces, but disassembled and reassembled everything, and let the laptop run for a week or so, sometimes moving it, flexing the chassis to induce the „Force off“ behaviour to make sure it's fine. And it's been working great since then.
I don't know if this is applicable to your newer machine, but my issue might have been some under-tightened screws inside that caused a momentary disconnect for some parts and the BIOS (or ASF2) issued a system restart (or a Force Off) to prevent something (idk, data corruption, system fault or something).