If you experience freezing, or see a "black screen" when trying to watch a video, game freezes or crashes while watching, or you do not receive rewards for watching, then you need to report this problem directly to the ad network that provides ad videos for the game.

You can do this while watching the ad. To submit a complaint, you need to tap the icon of the advertising network and submit a request (Report advertisement -> Report):

Please note that the advertisement icon and interface may vary depending on the provider.