In Monterey, the yellow dot that indicates microphone use is part of the Control Center icon. Yours is at the far right. Could yours be indicating something else or are you not on Monterey?
I had the same issue. I fixed it by installing the app OverSight that allows me to see which app is accessing the camera and microphone. As soon as I installed the app, the orange dot disappeared and I am now getting information on specific apps that use the camera and microphone.