My guess is there's an issue with the 5V circuit. Not sure why there would be, but if you're in the US and bought it from Eyeboot it traveled across the Pacific twice so something could have gotten jostled in shipping. The batch he received was tested for a full 3 days and power-cycled numerous times. Point of fact, I have yet to see one with a failed 5V circuit at any point in testing. But your symptoms sound like what would happen in that case.
What you should do is talk to Eyeboot about warranty work. If you can wait a bit I can repair it for you, but as noted above I'm breaking down my shop and moving to a new location this month so I wouldn't be able to look at it until after Thanksgiving, and either way you need to contact Eyeboot. The reseller is always the first point of contact for support.
Yes, I have already sent them a message about the situation and awaiting for a response.
If it is a problem with the 5V circuit, is it a “quick” fix with a few soldering tools and electrical parts?
I haven’t opened it up of course so warranty(if there’s any) wouldn’t be affected. I’m just curious if it would be something doable so it could cut us both a slack for both savings and time. I appreciate your offer! I will look forward to it if there’s no way I can do anything about it! Thank you so much! God bless!
BTW, I did have my Raspberry Pi 4 attached to its 5V USB port with no additional power but only the 200W 12V PSU powering it. Perhaps that’s the problem? I just don’t see how that would connect...?