I don't know how or why this happened, but that card with the phone number for Apple customer service was labeled as "my card" !! I didn't even know there was such a thing as "my card" in contacts; I've had a contact card for myself for a very long time and autofill was always working correctly, until recently. So there's some disconnect between the My Card info and the card I had set up with all my info.
My solution was to edit "My Card" (in Contacts on my iphone) and fill in all my personal information (and obviously put in my phone number instead of Apple customer service!), then delete the card I have had for many years.
I don't know why the macboook Contacts does not have something called My Card. Very confusing. But hopefully this issue will not happen again.
Check that the card labeled "My Card" has all your info. Good luck with resolving your issue.