What I got from helpdesk when I had the same issue.....
We believe we have a solution from our technical centre that should solve the problem:
Right-click at game screen and enter flash player general settings. There is storage setting in first section, there is local storage settings in bottom side. Click it and set to ''deny'' warofdragons.com site. Log in afterwards and refresh page, then go to the same option and set to ''allow'' the warofdragons.com site.
This video might be helpful to you -
https://www.youtube.com/watch?v=rRtJyoHDqBU.
Hopefully you will have no more problems with flash.