Hi there, @gcolorni.
Welcome to the Community. I'm here to ensure that you'll be able to connect your bank account with QuickBooks Online.
May I know what specific financial institution are you having issues with? If you've encountered errors while connecting your bank with QuickBooks, we can go ahead and perform some troubleshooting steps to get this sorted out.
First, let's run a manual update to refresh the connection of your bank and with QuickBooks.
If the issue persists after the running the manual update, you can check out this article for more troubleshooting steps in fixing online banking errors: Fix online banking errors in QuickBooks Online.
Also, if you could provide further details as to what specific error you're experiencing, I'd be here to provide additional information for you.
This should keep you moving today, @gcolorni.
I'll be on the lookout for your reply and look forward to further assisting you. Wishing you and your business continued success.