Stars are not rewarded immediately. It can take up to 48 hours to hit the Wiiny application.
You can try the following steps :
- For surveys and videos, If the stars are not credited on screen, go back to the main contest list and refresh it by doing a pull-to-refresh gesture.
- Try to restart the application, if there's still nothing, you can first send your complain to the publisher (for instance Fyber, Ironsource or other partners depending on the mission or the survey you did), they may be able to tell you where your stars are.
- Check your network and bandwidth, a bad network can also delay rewards.