https://www.bleepingcomputer.com/news/security/american-express-down-in-outage-users-report-login-and-payment-issues/

Yesterday, American Express users across the world including US, UK, and Europe, experienced widespread outages lasting hours. And, the payment services giant advises that some users may continue to experience issues online or over the phone.

The issues reported by users included being unable to log in to their Amex accounts, make payments, or get to an Amex customer service representative over the phone.