@angiemac: To begin with, please download and install the Fitbit app from the Google Play Store. Once installed, open the app, tap your profile picture, followed by your device image, and select 'On-Wrist Calls'.
Now, on the watch itself, please head to Settings > Vibration & Audio > On-wrist calls > Sense Controls/Calls. Furthermore, on your Galaxy S21, please head to Settings > Connections > Bluetooth > On > Select 'Sense Controls/Calls' in the available devices section. A number will appear on your phone, and when the same number appears on your watch, tap 'Pair'.
If you return to the Fitbit app, the pairing should be complete. Let me know how you get on.
