Enrollment of American Express card not complete yet
When someone other than the Card Member (eg. Accounts Payable employee of business who is not the Primary owner of the Card account) is enrolling an American Express card for a Vendor Pay account, the Card Member is sent an email with instructions to complete enrollment of the American Express card.
If the setup has not been completed by the Card Member yet, any other users attempting to log into the Vendor Pay account will encouter a screen that states: "Thanks! You're almost done - your Card Member needs to approve your setup first. We'll email you once it's approved."
To resolve, contact the Card Member to complete the setup. Once the setup is complete, all users will be able to log in to the Vendor Pay account.