Based on our research, there are several possible causes and solutions for this issue that you can try:
- Make sure that you have given Teams permission to access Nearby devices in your Android settings. This may help Teams recognize your Bluetooth headset. You can do this by going to Settings -> Apps -> Teams -> Permissions -> Allow all access (Must enable “Nearby devices”).
- Check the sound settings in Teams and make sure your Bluetooth headset is selected as the default device for both speaker and microphone.
- Clear the Teams cache from your device.
- Uninstall Teams from your device, then reinstall it.
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