If you are logged into your account and you are no longer seeing a specific ticket you previously saw, it is possible that the ticket has been resolved or closed and your view is currently set to only show "Open or Pending" tickets.
Example:
Click on the dropdown arrow to reveal the menu. You can select "All tickets" or "Resolved or Closed" to see additional tickets.
Once you have chosen a different view, you should see any tickets that have been marked as "Resolved or Closed."
Don't forget to change your view again or set it to "All Tickets" to see everything together.