Add New Contact Fails on MacBook Air and MacBook Pro

Hi jackleb82,

We'd recommend trying to add the contact while in safe mode to see if the issue still exists. If you are not familiar with the safe mode steps, you can follow the steps here: How to use safe mode on your Mac - Apple Support to get it done. Once in safe mode, you'd want to use the Mac as you normally would to see if the issue occurs again. You can tell when the Mac is in safe mode because on the desktop it will show the words Safe Boot in the top right-hand corner of the screen. The steps are also below.

"Apple silicon

1. Shut down your Mac.
2. Turn on your Mac and continue to press and hold the power button until you see the startup options window.
3. Select your startup disk, then press and hold the Shift key while clicking “Continue in Safe Mode.”
4. Log in to your Mac. You might be asked to log in again.

Intel processor

1. Turn on or restart your Mac, then immediately press and hold the Shift key as your Mac starts up.
2. Release the key when you see the login window, then log in to your Mac. 
3. You might be asked to log in again. On either the first or second login window, you should see ”Safe Boot” in the upper-right corner of the window."

Also, do you know if you are managing your contacts using a third party account or iCloud? You can view more details on that here: Add contacts from iCloud, Google, and more to Contacts on Mac - Apple Support

Best regards.