If you are having difficulty with your Poké Ball Plus, Pokémon GO Plus, or Pokémon GO Plus + device, removing the connection from your app and reconnecting it will resolve the issue in most cases.
To remove the connection:
In the Map View, tap the Main Menu button.
At the top right, tap the Settings button.
Tap Connected Devices and Services.
Tap Accessory Devices.
Tap the eject icon next to your device's name under the Available Devices menu.
Once you’ve disconnected your device from Pokémon GO, the connection icon will be removed from the Map View. To re-pair and connect the device, follow the instructions here.
Note that if you are in a crowded area, it may be difficult to establish the connection between your device and the Pokémon GO app, so you may want to move to a less crowded location before trying this step.
If this doesn’t resolve the issues you’re experiencing, try the following:
Exit to the Map View and re-enter the Accessory Devices menu.
Restart the Pokémon GO app
Uninstall and reinstall the Pokémon GO app
Restart your phone
Clear the list of connected devices from your phone
Factory reset the device
To factory reset your Pokémon GO Plus:
Press and hold the Main Button for 5 seconds. The indicator light will glow blue.
Press and hold the Main Button again for 5 seconds. The device will vibrate.
To factory reset your Poké Ball Plus:
Press and hold the white, front button and the red, top button simultaneously for 5 seconds. The indicator light will pulse.
Press the top, red button twice and the indicator light will flash white
Press and hold both the front, white button and red, top buttons simultaneously and continue to hold the two buttons until the device vibrates twice
To factory reset your Pokémon GO Plus +:
Press and hold the black, side button
While holding the black, side button, use something to press and hold the black indented button on the back.
While holding, wait for a short vibration and then a longer vibration to indicate the device has successfully been reset.
For additional troubleshooting tips, please see The Pokémon Company’s troubleshooting guides for the Poké Ball Plus, Pokémon GO Plus, and Pokémon GO Plus +.