If address book is the same as "contacts", no because I deleted the old number.

Originally Posted By: artie505
Is Messages maybe picking the number up from Address Book?

Edit: "Mavericks" may be too narrow a search term...excluding other OSs.

MacBook Pro - M2, Ventura 13.6
Safari Tech Prev 17.0
Safari 16.6
Firefox 116.0.2
iPhone 7 Version 15.8