Hello there, swiftwired.

Thanks for reaching out and letting us know about your experience with the online banking feature in QuickBooks Online (QBO).

I understand that you have already tried some troubleshooting steps to fix the error 4009 and confirmed that your bank's website is not undergoing maintenance. However, to resolve your banking concern, I recommend getting in touch with our Customer Care Team. They can access your account securely and conduct a screen-sharing session to identify the root cause of the problem.

To reach them, click the ? Help button at the top-right corner and select Contact Us to talk with a live agent. Ensure to review their support hours to know when agents are available.

Also, please note that disconnecting a connected bank account in QBO is not advisable as it can cause issues with your bank transactions, such as duplicate entries. 

To ensure hassle-free reconciliation of your account in the future, you may refer to our article on the best practices for the reconciliation workflow in QuickBooks. It also guides how to overcome challenges during the reconciliation process.

Please feel free to keep me updated if you have any other banking concerns. I'm here to assist you at all times!