It's my pleasure to help connect your new bank account to QuickBooks Online (QBO).
For me to verify and check for any open investigation, may I ask the name of your bank?
As of now, you need to try reconnecting your account using a private browser to help us determine if this is a browser-related issue. To open access QuickBooks using a private browser, you may use either of these shortcut keys:
Google Chrome, press CTRL+ Shift + N
Mozilla Firefox/Internet Explorer: Press CTRL+ Shift + P
Safari: press Command + Shift + N
If you're able to connect your bank account using a private browser, you may need to clear the cache of the regular browser you're using. Clearing it will refresh the system, and you'll be able to work with clean trash. However, if the issue persists, try using other supported browsers.