Hi Abdul_Moaz,
Welcome to Community! Not being able to access your QuickBooks Online account can be extremely concerning. I'd be happy to assist!
If you haven't done so already, I suggest clearing cache on your browser. Log into your QuickBooks Online account using your Primary Admin email address and password. If you're trying to login from a mobile device, please use a web browser.
Should you experience the same outcome, please don't hesitate to contact us. It would be our pleasure to work with you directly, and ensure you're back to business 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.
Feel free to reach back out with other questions. We'd be glad to help!