The following guide can be used to troubleshoot problems with the Streams functionality.
If you don't see the warning messages, and if clicking the Streams Panel icon doesn't show the new Streams Notification, then this is most probably an issue with the Subscription functionality. See here for the troubleshooting this issue.
This means that the web socket connection is terminated. If it is not resolved automatically after a few minutes open the Debug Console and check the log information in the Sub Category FndWebSocketService. Here are a couple of possible error you might see.
If you see a different error message please contact IFS.
Sometimes the Warning sign is not shown in Streams Panel, but push notification is not working as expected. If so check if there are any messages in the Oracle Queue CLIENT_NOTIF_Q, and that it's growing.