The Computing Unit turned into a brick for several hours

Hi! Today I had a very strange experience with a computing unit (dev kit). Unfortunately, I have to work with it at the request of the customer, although it is not supported by the current SDK. Today it was totaly charged and up to date. Periodically, the controller and glasses gradually start to work poorly with the unit, so before the demonstration I used to restart it with ‘adb reboot’. And then, five minutes before the demonstration to the customer, I also restart the unit. But after the reboot, wi-fi stopped working and refused to turn on. But the glasses worked. I reloaded the unit again using adb reboot.
And then a terrible thing happened. The unit began to blink green and did not connect to either the glasses or the computer. After a short time, the unit completely went out and did not respond to any actions. I was upset that the unit had completely turned into a brick. I put it down, and after about an hour I managed to turn it off by pressing the power button for a very long time. The pressing was about 20 seconds or more. After that, the unit booted up and works as if nothing had happened.
Any idea what it was? How to avoid such cases?

Hi, we need a log file to analyze and locate the issue. But you can try to hold the button for 15-20 s if you encounter the issue again and cannot get into the main menu of the computing unit.

I’ve had it where the computing unit wouldn’t respond at all. It had battery, but switched itself off, wouldn’t switch on, no lights when plugging in to charge. I thought it was dead. A few days later I tried plugging it in again and a light came on. I think it must have had a major crash and needed the battery to go flat to reset itself or the memory.

There’s other on here had the same issue, so you’re not alone