You perform some action in the system and receive the 'Error: 400 Session Timed Out'.
SAP Hybris Cloud for Customer
Reproducing the Issue
Several actions in the system can lead to this error.
This happens when your user is already logged in and a second login session for the same user (same username and password) logs in.
When the second user logs in then a dialog appears asking whether you want to delete all other sessions? If the second user selects Yes, then the first user will get this Time out dialog saying 'Session Timed Out.
Please confirm that nobody else is using your Username and password and if somebody is using yours credentials, then please ask the other user to select No in the dialog appearing.
Then this session timed out will not happen.
Please note that this might also be caused by yourself if you are logged into the system for example in more than one browser.
SAP Hybris Cloud for Customer Administrator Guide > Logon as Another User
Error 400 session timed out , KBA , AP-RC-UIF-ACC , UI Runtime Accessibility Issues , Problem