Authorizing American Express Card for online access always immediately failing

Alan5

When the connection method for American Express Card was first changed, I was successful in re-authorizing the new method. Subsequently, this authorization stopped working. When I try to Set Up Online again, I click the Sign In button to launch the external browser to authenticate to AMEX. However, when I click this button, I immediately receive the error:

"Sign into American Express bank failed. Try again

Sorry, the sign in failed due to time out or a connection error.

Select Sign In to authenticate via your web browser"

with the same Sign In button as before.

Clicking the Sign In button constantly results in this same error with virtually no time to have received an error message from a server.

UKR

What's your default web browser?
And have you tried using a different browser?