There main reason the HFP profile is not available is the Pulseaudio drivers have removed support for it. Any Bluetooth device can now only connect via A2DP configuration which does not support on-device microphone. I myself had the same problem and had spent around a week to figure out the solution that works without much hassle. You can follow the instruction mentioned at https://eternalgeek.in/index.php/2021/06/13/solving-mic-of-wireless-earbuds-not-working-on-ubuntu-20/
Till the time the support get added back into Pulseaudio I think this might come in handy. Hope this helps and save time at your end! -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to pulseaudio in Ubuntu. https://bugs.launchpad.net/bugs/1576559 Title: Refused to switch profile to headset_head_unit: Not connected Status in PulseAudio: Unknown Status in pulseaudio package in Ubuntu: Fix Committed Bug description: I'm trying to connect a bluetooth-speaker-with-microphone (Mi Bluetooth Speaker) to Ubuntu. It works well as an A2DP sync, but can't use it as a headset with microphone. The device doesn't list in the "Input Devices" by default, and using the sound settings to change the profile of the device to HSP/HFP results in this log message: W: [pulseaudio] module-bluez5-device.c: Refused to switch profile to headset_head_unit: Not connected I'm running Ubuntu 16.04 LTS. I did an upgrade from Ubuntu 15.10. pulseaudio: Installed: 1:8.0-0ubuntu3 bluez: Installed: 5.37-0ubuntu5 To manage notifications about this bug go to: https://bugs.launchpad.net/pulseaudio/+bug/1576559/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp