If your Toyota's microphone is not working, there are a few things you can try to fix the issue. First, check to make sure that the microphone is turned on in the car's settings. If it is turned on, then try restarting your car. Sometimes, a simple restart can fix audio issues.
If restarting your car doesn't work, then the next step is to clean the microphone. Microphones can get dirty over time, which can cause audio quality to degrade. To clean your Toyota's microphone, use a cotton swab dipped in rubbing alcohol. Gently wipe down the microphone mesh with the cotton swab until it is clean.
If cleaning the microphone doesn't improve audio quality, then there may be an issue with the car's audio system itself. In this case, you will need to take your car to a Toyota dealership or a qualified automotive stereo shop for diagnosis and repair.