Reset your watch Settings:
Note: Use the Galaxy Wearable app to reset a Galaxy Fit.
Depending on your watch, the reset methods may be a little different.
Navigate to Settings.
Swipe to and tap General.
Swipe to and tap Reset.
Tap the checkmark to start the reset.
For a Gear S2, swipe to and tap Gear info from Settings. Then, tap Reset Gear > Factory reset > Done.