[problem] I have to register/pair my Fenix 6 pro EVERYTIME ! (few times per day) Is it normal ????

Is it being removed from bluetooth devices? Then it is something with the phone. The Connect app can't remove bluetooth devices.

Got it. Try to delete all the activity from fenix, it worked for me

So the problem is with Pixel 7a 

Or with Fenix 6 pro ?

Mine edge 530 and 840 work normally.

Depends on the exact issue you are experiencing.

The tip above was to remove all activities on the device. 

after Fenix restart everything started to work normally (Before I restarted only my phone)

nope, it's still like this, for over 2 months !    IT HAPPENS ONLY WITH FENIX 6S PRO !

Edge 530, 840 and other devices work (and stay paired) correctly.

Had this with a Venu SQ2 Music and a Pixel 6a after I updated the Pixel6a to Android 13. Every time the phone came back into range of the watch I had to repair. The watch disapeared from my list of BT devices, although other paired devices remained - JBL, auto, helmet comms, headphones, etc. Painful.

Now switched to an Istinct 2 Solar, hoping the problem goes away!