Hi
This might be due to the following reasons:
Network connectivity issues: If there are problems with your internet connection, it could prevent the portal from loading.
High traffic: If many users are accessing the portal at the same time, this could cause it to slow down or become unresponsive.
Server issues: There could be problems with the servers that host the portal, which could cause it to become slow or unresponsive.
Browser issues: If you are experiencing issues with your browser, such as outdated software or too many extensions, it could affect the performance of the portal.
If the issue is with the Azure DevOps service itself, you can check the Azure DevOps status page
https://status.dev.azure.com/ to see if there are any known issues or planned maintenance that could be causing the problem.
If you are not able to resolve the issue, you can open a support ticket with Microsoft to investigate the issue further.