Can't add contacts using Contact app in Tahoe 26

I recently upgraded my Macbook Pro to Tahoe 26.1 and I now find it nearly impossible to enter a new contact on my Macbook using the Contacts app. I can do it easily on my iPhone, but when I try to enter a new contact on my Macbook, after I enter the name, then try to click to enter the phone number or email address, the new contact just completely disappears and the app shows me some other existing contact. This is super-frustrating! Have others encountered this? Is anyone at Apple working to fix this?