Mic not working when I answer or make calls through my iPhone on my MacBook Air

For over 6 months now I have not been able to make or answer phone calls on my MacBook Air M2 2022. When a call is active, I can hear the caller, but they cannot hear me. I was using Mac OS 15.6.1 until today when I upgraded to Tahoe 26.0.

I have checked all my sound input settings and phone and FaceTime settings and they are all OK. When I'm in Sound input settings and I speak, graphic goes up and down to indicate that the mic is picking up my voice and the mic works when I make recordings or videos, just not on phone calls. If I use my headphones, I can talk and be heard, but not when I'm using the built in mic on the MacBook. I have tried everything I can think of and have tried all the solutions I've found when looking through the Community. Can someone help me please?