SHELL

bluetooth linux protocol not available

sudo pacman -S pulseaudio-bluetooth
pulseaudio -k

ubuntu bluetooth Protocol not available

# reinstall bluetooth
sudo apt --purge --reinstall install bluetooth bluez blueman pulseaudio pulseaudio-module-bluetooth

# at
sudo nano /etc/pulse/default.pa

# add load-module module-bluez5-discover

# then
sudo killall pulseaudio
pulseaudio --start
sudo systemctl restart bluetooth.service