If FaceTime isn't working on your Mac
If you use your camera or mic, can't stay connected or can't sign in, find out what to do.
If your camera or microphone isn't working
Close FaceTime, then open FaceTime again.
Restart your Mac.
Make sure FaceTime isn't open, then see if your camera is working in another app, such as Photo Booth. If it isn't, you'll know it's not an issue with FaceTime.
If you have multiple cameras or microphones connected to your Mac, check the Video menu in the FaceTime menu bar to make sure the correct camera and microphone are selected.
If the issue involves your computer's built-in camera, find out how to resolve issues with the built-in camera.
If the issue involves iPhone when used as a webcam, consult Continuity Camera: Use your iPhone as a webcam for Mac.
If you need help with your connection or call quality
A slow or busy Wi-Fi network may cause issues with your FaceTime call. If you experience connection alerts, or low-quality audio or video, or an exclamation mark
over a video tile:
Make sure you and your recipient have a fast Wi-Fi or mobile connection. FaceTime calls over Wi-Fi require a broadband connection.
Check for issues that may be slowing down your connection, such as someone streaming content over your network.
If you have any questions about your internet speed, contact your internet service provider.