Hi DECKER, JOHN M,
Thank you for reaching out to Microsoft Q & A forum.
We understand that you are currently experiencing difficulties concerning the login process for the sandbox environment.
If you encounter difficulties when attempting to access a sandbox environment using your work email e.g.: att.com work email, and the login page repeatedly refreshes without providing any error message or granting access, there may be multiple underlying causes for this behavior. To address this issue effectively, it is recommended to follow these troubleshooting steps:
1. Sign out of your att.com email account on all devices and programs where you may be currently logged in.
2. Clear your web browser's cache and cookies to ensure a clean and uncluttered browsing environment.
3. Restart your web browser to implement the changes effectively.
4. Reattempt to sign into your att.com email account within the sandbox environment.
Should you continue to encounter the issue, please do not hesitate to reach out to us.
If you have found the answer provided to be helpful, please click on the "Accept answer" button so that it is useful for other members in the Microsoft Q&A community.