We are aware of rare issues involving our advert videos.
You may see a "Playback Stopped" error message, you may not receive your reward or your game may crash.
The development team is aware of these issues and is currently working with our external advert providers to resolve them. Unfortunately, this does mean watching adverts for rewards may not work correctly from time to time.
We apologize for the inconvenience, please feel free to submit a support ticket and we will keep you up to date with information regarding a fix.