Send us an email from the Support Menu (Settings > Support). It should automatically include your support token for us to look into why your progress was not restored. If possible, please share with us exactly what you did before your lost your progress.
To safe guard your progress in general, we strongly recommend authenticating/connecting the game to Facebook (Settings > Facebook Connect). This will ensure that even on app deletion, you are able to restore your progress by reconnecting Facebook. You will be given an opportunity to continue the game / download your progress from the server.