How to update outdated contact information in Safari's auto-fill on macOS Sequoia?

On several occasions, not every time, when I try to use the dropdown contact fill-in the information is very old. When I recently tried to fill in my information for a gov website the contact info auto populated with an old PO Box address that I haven't used in years and is not in my address book or contact app. So I'm not sure how to change it. When I click on the Customize link at the bottom of the auto populate window the PO Box also doesn't show up, so this is weird. Somewhere on my computer the PO Box is stored but I can't seem to delete it.

Browser: Safari

macOS: Sequoia 15.1.1.

Please help, thanks.

[Re-Titled by Moderator]