Same problem different day, week, month

INSPIRON 15 3520 (Windows 11 Home

<edited to add PM model and version of Windows>

 The nightmare began 8/22/23. Though I had received this laptop as a gift for Christmas, I had not yet used it on a consistent basis- an hour here and there and, for the most part, while it was plugged in. When I started to use it as a laptop, unplugged, the issues with random shut downs began. Neither Costco technicians or Dell remote access could ascertain the problem, and because it was blinking at the  cable -white and amber lights  it was sent away to Texas to be fixed.

Within 2 weeks, the computer started shutting own again, always shutting down when fully charged and unplugged.

Nothing works via the 3 different techs that had remote access. Once again the lights are flashing- 1 white, 4 amber. Send it back to Texas, but this time to the  Advanced resolution center at dell. Meanwhile, another week without my laptop and countless hours lost on the phone.

<Private data removed from public view. DELL-Admin>

I am not sure what cables were replaced as I have before and after pictures of the exterior cables and they are the same. Anyway, within hours it was clear that nothing was fixed as the same exact issue persisted.