Within 1 day of setting up a connection to my iPhone or iPad, the vivoactive 4 loses Bluetooth connection. In contrast, my Fitbit remains connected. So I don't think its the Bluetooth.
This is despite following online advice of checking latest firmware on watch using Garmin express, removing watch and re adding watch. Restarting watch. Restarting iPad / iPhone.
All in one sequence. This procedure has become tedious as I have to repeat each day, so I don't lose my timings