Since I got my 6s Siri stopped working on my Watch. So I wiped the Watch, did a clean install. Sacrificed all my fitness data - and nope, still no Siri. When I activate Siri on the Watch it says something like "Siri cannot get a connection on your Watch or your iPhone." But Hey Siri, and all things Siri, work FLAWLESSLY on my 6s. I have Apple Care, should I lose HOURS of my life and go in? Or wait and hope it gets better. Thanks!
Watch will respond, at least most of the time. They will both occasionally respond together but not often. I have had it happen maybe twice.