Hello, I have the same problem. I haven't found a reliable solution yet.

I have similar problems and so do my work colleagues. It happens again and again that when I am called on my mobile during a Teams call on the PC/Mac, the other person can't hear me for the duration of the ringing. The only remedy is to decouple the headset from the mobile. It seems to be a well-known problem.
I don't use the dongle at all and pair my Noteboosk and mobile via Bluetooth.