Let me help you with looking up your bank when connecting it to online banking in QuickBooks Online (QBO). 

I have a few steps you can take to help you resolve the missing bank account when connecting it to online banking. This might be a simple webpage sync issue, so we can refresh the Banking page by pressing the F5 button. Another thing to try is we can to sign out and sign back in.  This unexpected behavior can also be caused by a cache-related issue. When a browser's cache is full or corrupted, it can cause several issues within QuickBooks. One way to rule this out is to use an incognito or private browser. Here's how: 

• Google Chrome: CTRL + Shift + N.
• Microsoft Edge: CTRL + Shift + N
• Mozilla Firefox: CTRL + Shift + P
• Safari (new versions): Command + Shift + N

Once done, we can log back into your QuickBooks account and check the bank account under the Banking tab. When they appear properly, go back to the regular browser and clear the cache. This will clear the webpage data that's causing the issue. Then, close out any browser instances to complete the process. Alternatively, you can use another supported browser to check your connected accounts. 

If the same thing, you can check out this article for more some troubleshooting steps to resolve the issue: Find your bank account when you connect to online banking. Also, when reconnecting a financial institution, make sure you enter the correct bank name or URL. Otherwise, you'll want to check with your bank website and verify if there is any message that requires action from you.

Once done, try reconnecting your bank account again. Read through this article for more details about connecting your bank in QBO: Connecting and adding bank and credit card accounts to QuickBooks Online.

You might also want to visit this article for your next task after connecting your bank account to QBO: Categorize and match online bank transactions in QuickBooks Online.

I've got your back if you have more questions about connecting your banking transactions in QuickBooks Online. If you need help with reconciling your bank accounts, just leave a comment below. I'll get back to you.