Hello char604,
Thanks for asking the Apple Support Communities for help with faceTime on your Mac computer. I will be happy to check this out with you.
1. First, please verify your computer is updated to macOS Mojave 10.14.3 (build 18D109 or later) for Mac. This article will help you update macOS: How to update the software on your Mac - Apple Support
2. Next, please verify the info and troubleshooting in this article: If FaceTime isn't working on your Mac - Apple Support
3. Lastly, if you still need help, I recommend trying the troubleshooting provided in this help article: macOS Mojave - If an app freezes or quits unexpectedly - Apple Support
Thanks and have a wonderful day.