Unable to add offers to new/replacement Amex cards

If you are unable to add Amex Offers to a brand new or replacement Amex card that you just got, that’s due to a weird bug on Amex’s side — one server says that offers are available on the card, but when you try to actually add them, another server says that the offer has already been added and won’t add them.

You can check if this is happening by clicking the “Add Offer” button on Amex’s site directly, and you’ll see an error on their site if you’re impacted.

This can also cause the extension to look like it’s going in an endless loop. To continue adding offers to other cards, you can open the extension's Settings tab and change the Offers selector to "Auto-Open" or "Manual".

After you wait a few days (up to 10 days at worst it seems), Amex will again sync everything up for the new card, then you can auto-add your offers like usual afterwards.