Vuforia View Crashes: Got unknown content type from server, UNKNOWN SERVER ERROR!

I have number of published experiences which were working perfectly yesterday. It's animated instructions step by step. Today all of sudden when I try to view the experiences  and move between steps the View app crashes. Sometimes from the first step, and others from second, third.

I tried to use different trial account and publish the experience again, that doesn't resolve the problem.

I tried Vuforia View on Android phone, tables and ios phone as well. All produce the same issue.

I checked the log file found: 

Got unknown content type from server, UNKNOWN SERVER ERROR!

Any help?

Attached is the log file from Android phone.