If you are unable to locate your cases. You can also check to see under My Cases tab --> "All Company open Cases".
I've noticed this happens with Chrome more frequently than anything else. One thing you'd like to check for is if you have the latest version of Chrome.
Otherwise, as everyone else suggested, try a different browser, get to the tickets differently, or email support if the first two don't work.
Same thing on all browsers, will just send them an email
Thanks for you feedback