Issues with Amex in Apple wallet

Has anyone else come across the issue where their Amex contactless works perfectly fine on their physical card, but when they scan it on their Apple wallet it immediately declines? I’ve tried updating my phone, removing the card from my Apple wallet and putting it back on, signing out of my iCloud, but nothing seems to have helped. I only started using an amex for about a week before this started happening out of the blue. Any advice? I’ve talked to Amex and Apple but both say they can’t do anything.