I can not connect with bank

Try opening your QBO account on any private/incognito browser.

Hi wangxi7890-gmail,

Thanks for reaching out here.  Connecting your bank and credit card accounts to QuickBooks Online is a valuable time saver, in keeping your books balanced.  It's important that you're able to connect your accounts without delay!  In this situation, I recommend clearing cache on your browser, or try other browsers such as Google Chrome, Firefox, Safari, or Edge.  If the issue persists, I suggest contacting us outside of Community.  Our Customer Care team will be able to look into your situation in more depth, and ensure you're able to get connected as soon as possible!

Schedule a Callback or start a Chat: click (?) Help in the upper right in QuickBooks Online > enter "Contact support" > hit Contact Us > provide a brief summary of your situation > hit Let's Talk > choose Get a callback or Start a Chat.
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Support hours are from Monday to Friday between 9 a.m. and 8 p.m. ET.

If you have any other questions, feel free to reach back out.  We'd be happy to help!