Thank you for bringing this to our attention. It's my priority that you're able to connect the bank account in QuickBooks Online (QBO).
Our engineers are aware of this and are currently investigating the particular occurrence. While they are still working on this, you can bring transactions into QBO if your bank offers a valid WebConnect download file.
For now, I'd suggest contacting one of our phone agents so that they can add you to a notification list. You can reach them through this link: https://community.intuit.com/articles/1145770.
Rest assured that updates will be given to you once this gets resolved. From there, you'll be able to connect your bank account in QBO.
Thanks for your understanding and patience. You can always visit the Community site if you have other concerns, or if there’s anything else you need. I'm always here to help.