Not sure where to post but I suspect an android / app issue rather than hardware...
I have a Xiaomi mi mix 2s and forerunner 645m. It's normally fine but the past week or two I get multiple vibrations for the same notification on my watch. The watch screen will show the notification, vanish, appear, vanish etc for up to 6 times. I thought this was isolated to WhatsApp messages but also had it from HotUKDeals app too.
I've checked for battery optimisation and notifications and they all seem normal.
Any help appreciated!