FaceTime on macOS cannot connect to camera, but all other apps can
People upgrading to iOS 13.4 or macOS Catalina 10.15.4 have found that their devices can no longer connect to older iOS devices running iOS 9.3.6 or earlier or Macs running OS X El Capitan or earlier. Some say the problem also occurs when trying to call people using versions of iOS 10. And others have found this problem when using a Mac with macOS Catalina 10.15.4 for older versions of iOS and OS X versions.
With this problem, Facetime gets stuck in a &quot;connection&quot; for both incoming and outgoing calls.
To fix these issues, upgrade to iOS and iPadOS 13.4.1 or higher. For Macs running macOS Catalina, update macOS to the latest version of macOS (Apple has released an additional update for macOS Catalina 10.15.4.)
Apple says the problem has been fixed in these versions and above.