My phone always uses its own mic instead of the mics on the galaxy buds on every application but normal phone calls. In Bluetooth settings the only two options are audio and calls which are enabled. I have disconnected and re connected the earbuds via the app, reset them via the app, turned Bluetooth off and on again and the firmware is up to date. I can't use Bixby or Google assistant without having the phone near me, they only work if I set the touchpad hold function to voice assistant, then the mic will work. Samsung customer services' troubleshooting didn't do anything either. I've also tried on other Samsung devices and still nothing. Hope someone can help
I'm in the same boat. Supposedly this functionally was added by an update last April, but I can't get it to work and would really love if it did work. I drive a motorcycle, do speaking into the phone isn't possible, but if I could have control of my phone through the buds mic thanks to hi bixby, that would be great.