XPS15 9500 turns on, shows DELL logo, then turns off.

What happened: While using, screen showed a low battery power notification and then, after maybe 1-2 seconds, automatically shut down. Surprised, I felt the keyboard which was fairly warm to the touch - almost hot even - despite not running any power-intensive applications. I waited maybe 10 minutes to give it plenty of time to cool down and then power it back up. 

Once turned on, the DELL logo shows and then, after maybe 2 seconds, the laptop automatically turns off again. I’ve tried entering UEFI but with no luck. This includes pressing F2 as well as holding the function key and pressing F2. Nothing happens and, each time, the laptop automatically turns off after about 2 seconds. 

Situation: laptop plugged in with original DELL power supply. Only active app was Star Wars Galaxy of Heroes (not power intensive) with maybe 7-8 background apps, the most intensive of which would have been iCloud. I use Windows Defender and there was no ongoing scan when this occurred. 

I have an HP dock attached to one USB-C port but it’s only used for external monitors and other accessories. All power comes through the OEM DELL brick. 

I purchased the laptop new in 2021.