Can't add guest order to Apple ID

I recently placed an order on the Apple website but turns out I was not logged in.

I did pay using Apple Pay so I assumed the order would be linked to my Apple ID but it is not.

When I check the order status, I see the following:

"Your guest order at a glance.

Add this order to your Apple ID to make changes or to return or cancel an item."

And then a big blue button below that says "Add to Apple ID".

When I click that button, I'm taken to a page that says:

"Something went wrong.

There was a problem with your request. Please try again."

I've tried following the link in the order confirmation email I received from several different devices. I've also tried logging into my account on the Apple Store website and then clicked on "Orders" and then clicking on "Don’t see your order?Find it now".

Nothing that I've tried as worked, it all results in ending up at a page that says:

"Something went wrong.

There was a problem with your request. Please try again."

Does anyone have any suggestions?