I'm not from the official support team, but here are some things I can think of, that may or may not help with the issue.

Looking around a bit, that particular code usually seems to have come up during temporary issues. The 5 minute wait especially makes me think of connection issues of some kind.

Also, is the error code actually accompanied with the payment method related message, or are they displayed separate? The note about the credit card seems "non-fatal" in that I can't imagine it preventing you from logging in, but would rather be there for informational purposes.

If the issue is still on-going, and you're not able to try with a completely different internet connection, I'd recommend you to be in direct contact with the support since they normally will not handle anything payment/account related here. Hopefully they'll be able to confirm that it's not account related.

Good luck!

Links to the support centre contact pages:

EU: https://support.eu.square-enix.com/c...hp?id=455&la=2

US: https://support.na.square-enix.com/c...php?id=20&la=1