Just tried to renew again and now getting a different error code. Now I'm getting:

"ERROR (-24202)
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No other information is provided. I googled the error and it says:
"The (-24202) error is a technical error that occurs because temporary files, extensions or add-ons that browsers use interferes with the actions taken by the web site. Please change web browsers or delete cookies on your default browser."

I attempted it twice on safari and I checked and I have 0 extensions installed. So, it's not the 601 error, but still unable to add my card back. And I haven't tried since the last time I posted, so it couldn't be the "wait 2 full days before trying" issue.