Prizes will be awarded once the Trial of Style ends. Keep playing to make sure you have the highest score possible before the event ends!
Once the event has completed it can take a bit for the prizes to award so be sure to give it a few hours afterwards (you may also want to restart the app to ensure it is properly synched with the server).
We have also received reports that changing the time on your device can cause prizes not to award as there is confusion between your device and the servers please avoid altering the time on your device during an event or before you claim prizes.