Yup do the live chat they should be able to fix it
Sent from my Galaxy Note 5!
It was just like in your case, they need to register my Note 5 to replace the S6 Edge on thir system, the guy took my information and he needs to escalate it and wait for the tech department to complete the process, and then I'm supposed to be able to get the update on the Note.
Related to the Amex that is failing, they told me that I needed to clear cache and data from Samsung Pay and Clear Cache from Samsung Pay Framework and reboot but it didn't fix it, he didn't tell me that the Amex were not accepted and he told me that I need to wait until I get it on the Note to see if it fails in there too, he thinks that it may be the app on the edge. But because I need to wait for them to register my Note on the system, I won't be able to know until then, I'll let you know later.