Hello @mbusbusiness
Thank you for reaching out to the Community regarding your issue, although I am sorry to hear that you are experiencing an issue with your 5/3rd bank accounts. It seems like the issue could be related to the one we're currently experiencing. Both have issues with sign-in information errors that are similar. With it still being a different error, I'd recommend taking a look at the troubleshooting article for the error you're experiencing. I'll leave a link to the 393 troubleshooting article down below.
https://www.quicken.com/support/message-when-using-quicken-online-services-ol-393
Let us know if you're able to connect or if you're still having difficulty.
Thanks,
Quicken Francisco