1. Check your internet connection to ensure that you have a stable and strong connection before starting your screen share.
2. Ensure that screen sharing is enabled on your Teams channel, and that the 'Allow Attendees to Share' option is enabled.
3. Check that the settings are correct on the device you're trying to share from, such as your microphone, speaker, and camera.
4. Ensure that the application or web page you're trying to share is running in the foreground on your device.
5. If you are still having problems screen sharing, try restarting your device to see if that resolves the issue.