Please follow these steps to get answers to your issues:

  1. Check Operational Announcements if this is a known or scheduled situation.
  2. Check available documentation, especially How Tos, FAQs, and other Documentation.
  3. Search for a solution within this site:
  4. Depending on your Jacobs University membership status,

Server Maintenance Hours are each Thursday, from 07:00-08:00. Also for HCM/Loga each Monday from 09:00 to 09:30!

During these times, server operation is unreliable. You should expect unavailable servers and sudden downtimes of services without prior explicit announcement.

See here for details.