Try these fixes in order until you can use your mic on Zoom:
1) Make sure your mic is connected and turned on.
If using an external mic, examine the connecting cable, or check your Bluetooth settings using a wireless mic. For wired mics, try plugging it into a different USB port. For Bluetooth devices, make sure you have a fully charged battery.
2) Select Join Audio.
Zoom usually requests access to your mic before you join a meeting, but in case you missed it, you can select Join Audio at the bottom of the Zoom window.
3) Make sure Zoom hasn’t muted you.
If the microphone icon has a line through it in your Zoom window, select the Sound icon to unmute yourself.
4) Make sure you’ve selected your microphone.
During a meeting, select the up arrow next to the Microphone icon and make sure the desired mic is active.
If other people can hear you, but you can’t hear them
Make sure the right speaker is active under “Select a Speaker.”
1) Ask the meeting organizer to unmute you.
If you think the meeting host has inadvertently muted you, send them a message in chat and ask to be unmuted.
2) Check your device settings.
Go to the device’s settings to enable your mic. Ensure you correctly set up your mic in Windows and select the audio input you prefer on Mac.
3) Close other programs that use your mic.
Make sure other software isn’t competing for access to your microphone.
4) Check your app permissions.
Go into your device’s app settings and make sure Zoom has permission to access your microphone.
5) Update your device’s drivers.
If you’re using Windows, go into the Device Manager to ensure your mic’s drivers are up-to-date.
6) Reboot your device.
The reason why rebooting resolves computer problems is that it closes any processes that might be interfering with hardware or software.
7) Mute other nearby audio devices.
If you hear an echo, your microphone may be picking up the audio from another source, such as a TV or an external speaker. To avoid hearing an echo in Zoom, everyone should mute their mic when not speaking. Meeting organizers can mute everyone else in the meeting.
Adjust Zoom’s Advanced Audio Settings.
Zoom offers advanced tools intended to improve audio playback, but they can sometimes have the opposite effect. If you have ongoing audio problems with your mic, open Zoom while not in a meeting and select the Settings gear, then choose the Audio tab and select Advanced to change these options.
Uninstall and reinstall the Zoom client.
If using the mobile or desktop versions, uninstall Zoom and redownload it from the Apple App Store, Google Play, or the Zoom website. If your microphone still isn’t working, you can join a Zoom meeting by phone. With this method, you can mute your computer so that it doesn’t interfere with the audio.