TRACKING doesn't start on WEAR OS /cant connect (FOSSIL SPORT)

no matter if i start the tracing on the phone or the watch, it will not “connect” to the phone for sleep tracking / smart alarm
The watch is paired with the google wear os app and everything workes flawelessly and instantaneous (notifications, etc)
I turned on all the wearable settings and went deep into android settings to turn off all possible power saving and battery optimisation modes
(my phone is a oneplus 6)

it’s the main reason i bought the watch…
thanks for your help

I’ve used Sleep as Android with a Sony Smartwatch 3 and a LG Watch Style. I wish I had a suggestion but I’m just as stumped as you are.