It's such a bullshit though. It's all 18650's on the inside, and there's no reason you shouldn't be able to just swap them out. It's just they are dangerous if shorted (but not as dangerous as powertools), and the actual cell manufacturers just want to shift liability on the end-user device manufacturers, so they won't officially sell them to you. And the latter of course love this because it makes it easy to vendor-lock you in.

Solution - buy batteries off aliexpress and the likes. I'm pretty sure the Chinese folk have it all figured out a long time ago, probably even have the adapters for every brand. Alternative, take dead batteries to your local electronics repair shop, they are likely to be able to perform the swap. Disclaimer: I'm not a handyman, this is not a legal advice or whatever, just chiming in from a field with similar issues.