When I wish to call someone using FaceTime video, the video button fails to light up. Yet, Siri can connect the call using video. How do I get the Video button to light up for use?

Hi philip_,

If you have restarted your Mac and the issue persists, let's try to narrow this down and isolate it more by testing in safe mode and a new user account.

Safe mode prevents certain software from opening and also forces the computer to run some disk checks similar to First Aid. This can actually resolve some issues. More information on starting to safe mode and steps to take after starting there can be found here: Start up your Mac in safe mode – Apple Support

"Start up your Intel-based Mac in safe mode

1. Turn on or restart your Mac, then immediately press and hold the Shift key until you see the login window.
2. Log in to your Mac.
3. You might be asked to log in again.
4. On either the first or second login window, you should see “Safe Boot” in the menu bar.

Verify your Mac started up in safe mode

If you’re unsure whether your Mac started up in safe mode, you can use the System Information app to check the mode.

1. On your Mac, press and hold the Option key, then choose Apple menu  > System Information.
2. In the System Information app, select Software in the sidebar.
3. In the System Software Overview, look at the value listed next to the item labelled Boot Mode.

• Safe: The Mac is using safe mode.
• Normal: The Mac is not using safe mode."

If the issue continues after the steps from safe mode, create a new user account (administrator) to see if the behavior happens there. This will let us know if it is system-wide or something within your user account: Change User settings on Mac – Apple Support

Delete a user or group on Mac – Apple Support (to remove the test account once completed)

Let us know what you find.

Cheers!