[EDIT 9 December 2020] Thank you for your patience while we looked into this issue. We have recently released a new update (version 34) which we hope will resolve this issue. Please update to the newest version of the game as soon as possible. If you are still experiencing this issue after updating to the newest version, please don't hesitate to contact us.
There is currently a known issue which is causing some players to not receive rewards after viewing some Mystic Vision Ads. We are investigating the issue here and hope to get it resolved as soon as possible. In the meantime, we recommend that players experiencing this issue, try to fully close and restart their app in order to establish a fresh connection to the server. Thank you for your patience and our apologies for the inconvenience caused by this!