If your device is not working, follow these steps to ensure the full driver set is active: Open Settings > Update & Security > Windows Update .

: Sites like DriverDouble list version 4.2.8 for older Windows versions, though caution is advised with third-party driver sites.

If the Bluetooth button doesn't appear in Windows, the system may be treating the BR21 solely as an audio interface. Check the Sound Control Panel to ensure the "Jieli BR21" is set as the default playback/recording device. Advanced Tools for Developers

It's USB sound card. Bluetooth inside is only for receiving audio stream from something like PC or smartphone and playing. Ask Ubuntu JieLi BR21 driver - DriverDouble.com

If you're looking to install or use the Jieli BR21 driver, here are some general steps that might apply: