Agentforce Testing Center => Use AI to Generate Tests, stuck generating test case

Hi,  

I am trying to complete Agentforce Testing Center => Use AI to Generate Tests, but I am stuck at step #14.

I have tried creating a new trial org but same issue.  I have seen few folks having the same issue 

, but there is no resolution yet.  

Does somebody has any idea how to pass this step? Do we need special permission?  

Thanks, 

Kilic