There are times that cache or browser issues can cause errors and delays in QuickBooks Online, bfgs2009.
This can be the reason why you're unable to reconnect your bank account. Have you tried re-authorizing your bank account in an incognito/private browsing session or switch a different browser.
If not, follow these keyboard shortcuts to start an incognito session:
Then, log back in and reauthorize or reconnect your account to check if that would go through. If it's going through, delete your browsing history that might have caused the issue. This permanently deletes the stored cache that's causing the issue.
Here's an article as a guide: Clear Cache And Cookies To Fix Issues When Using QuickBooks Online.
Just in case you need more references when working in the Online Banking section, let me share these articles with you:
Join us again in the Community if you have other QuickBooks-related inquiries. We're always here to make sure they're all taken care of.
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