WAZA-AIR BASS: In the Bluetooth settings of BOSS TONE STUDIO, "WAZA-AIR BASS MIDI" is not shown in CONNECT.

It might be that "WAZA-AIR BASS MIDI" is connected in the Bluetooth settings of the mobile device.

End the "WAZA-AIR BASS MIDI" connection, and then pair once again using the procedure described in "Connecting the BOSS TONE STUDIO iOS (or Android) App to the WAZA-AIR BASS Unit" (PDF).