When I saw it was called "Muse headband", I immediately thought it was a Meta thing. Surely, it's just a matter of time until Meta knocks on their door. Especially if they're getting into the AI category with their supposed 'wellness devices'.
Either way, there will be an issue.
If you’ve been using a name earlier, ideally with a trademark but even without a trademark, and a big company also uses it after you; it’s generally their problem, not yours, and you can expect a wad of cash.