When you get PPP018 Error but device is working just fine.

I was running diagnostics on my Mac (holding the power button and then Command + D to run Diagnostics). I found out that I had PPP018 Error on my Mac, thinking I had power adapter issues. I found out upon testing on different cables and adapters/bricks that because I was using a GaN Charger I was getting that error message and when I used the factory charger on my Mac, I did not get any such messages upon doing the diagnostics, although the senior advisors saw the system and said that everything looks fine and that GaN chargers are safe. I am still on the research: if it is actually safe to use and if so, why am I getting that message after the Diagnostics?