Hi!
Have you tried to change another microphone device? Can it work on your Teams?
Is this microphone works in other applications?
Please make sure you have allowed Teams app to access your microphone.
Besides, we recommend you try to reinstall the drivers and re-add the device to Teams. If the issue persists, please try to repair your Office - Control panel> Programs> Programs and features> select Office 365> Change> Repair> Quick repair.