I appreciate you for reporting this to us immediately, @quickbooks12.
We'll take some troubleshooting steps to improve the program's performance and fix the problem with your denied access.
Let's start by clearing your browser's cache to refresh your browser. Sometimes, old or corrupted files in your cache or cookies can cause web pages to load incorrectly, which might be why your access is being denied.
Alternatively, we can try using a different supported browser to see if the issue is specific to the browser you are currently using.
If the issue persists, you can reach out to the Support Team without logging in to your QBO account by clicking on this link: Get help with QuickBooks products and services.
Additionally, if you need to change your sign-in information for your Intuit Account, this article may be helpful: Update your account credentials.
You can always revisit this thread if you have further inquiries about your QuickBooks access or any other QuickBooks-related concerns. My team and I are always here to support you.