Sense 2 not seen on iphone

[MOKehinde]

My Sense 2 suddenly stopped syncing to my iPhone. I have unpaired and repaired and phone no longer able to see the watch!

[FatimaFitbit]

Hi there @MOKehinde! A warm welcome to the Fitbit Community!

Thank you so much for letting us know about this situation. 

I suggest you try to do the following:

1. Turn off Bluetooth on your phone; wait 10 seconds, and then turn it back on.
2. Restart your Sense 2: Press and hold the button for 10 seconds until the Fitbit logo appears on the screen, and then release the button.
3. Turn your phone off and back on.
4. Remove all other Fitbit devices from your Fitbit account. For instructions, see How do I set up my Fitbit device?
5. Remove your Fitbit device from the list of connected Bluetooth devices on your phone or tablet:
   1. On your phone, tap Settings  > Bluetooth.
   2. Tap the information icon  or gear icon  next to the name of your Fitbit device.
   3. Find the option to forget the device.
6. Try setting up your device again.
7. Uninstall and reinstall the Fitbit app. Note: Before you uninstall the app, verify that your phone is running a supported version of Android OS or iOS. If your phone is on an older version, you won’t be able to reinstall the app. For OS requirements, see Fitbit-compatible devices.

Have you already checked if you can update the Fitbit app? 

[MOKehinde]

Thanks, FatimaFitbit. Followed all your suggestions but still can't connect the device with the Fitbit app in my phone. The error massage is 'something went wrong'.