The same thing literally just happened to me over this weekend. I had it plugged into a charger, and it shut off mid-game while playing in PCVR. When I booted it back up, it was in low-battery mode and turned back off, so I re-seated the charging cable and tried again. After half an hour of charging it was still in the battery-too-low-to-boot mode. Eventually it wouldn't even show the low-battery (charging icon) screen and only had a flashing red LED indicator. Then that stopped. I tried my 65W charger that was working with it before, my Steam Deck charger (45W), and even a slow charge overnight from USB-A to -C as others have suggested.

It took 3 days of back and forth with customer service having me try everything I've already tried (make sure charger is 45W, disconnect and reconnect the battery, etc.) but they're finally approving the RMA. I'm just waiting on the shipping label now. I'm glad I kept the box it shipped in.

I've had my Frame for about a month.

Edit: sorry for all the posts, I kept getting a connection error failed to post comment thing but I guess it was posting it anyway.

On the steam deck, you can force the device into battery saver mode, which will sometimes revive a dead steam deck. I don't know of a similar shortcut for the steam frame, and I'm assuming you've already tried and failed to enter Bios/UEFI power menu. You might ask steam support if there's a hardware shortcut for it (and if there is, please share it).

I can't speak to the RMA process for the Frame, but my limited edition white Steam Deck needed to be sent in, I think months after you were no longer able to buy the white one (and it was probably my fault it broke).

They sent me a brand new one. Limited edition white.

Valve's customer service has been exceptional in my experience.

Weirdly I've heard that this is sometimes tied to tbe IPD lock, and some folks have had success in booting it back up after unlocking it. I don't have mine just yet thanks to a shipping delay so I can't exactly confirm or deny, but I've heard that floating around. Trying to mentally prep for any potential RMAs myself 👁️👄👁️

I've had similar issues, where the Frame would shut down and not charge, although, the device would still have some charge left, I kept the power button pressed long enough (maybe 30-60s) and then the frame turn back on with 40% charge....

Not sure if this is the same problem here, but maybe try that?

This is really sad news :( I had hoped that Valve's Frame would keep running and not hit these sorts of dead ends. How comfortable are you with opening up the battery in the back? IFixit was able to get it off (and out) here: https://vr.org/articles/steam-frame-ifixit-teardown-battery-glued-fan-2026. If it were me, I would open it up and make sure all the connections still had good contact.