Well... it's the end of January and this issue has been around for a couple years.
I'm confused because someone said they updated to Watch OS 10.2 in Dec 2023, but it only became available now, end of January, 2024. I just updated to Watch OS 10.2 and iOS 17.3 on my iPhone yesterday.
Anyway... I still have the problem. I've contacted my charger manufacturer but no response. There's something else going on because NOT all 3rd party chargers are having issues, nor even within a single make or model. Meaning... others who have my charger aren't all having this problem.
[edit] Oh... I have S4 watch, and iPhone 12 pro - again... both with the very lates OS's as of writing.
[edit 2] Another (closed) post regarding this from 2022: https://discussions.apple.com/thread/253501605?sortBy=best