At the end of teir 4 races I was unable to recieve gold. I even made a purchase but the app took the money with no gold in return. I uninstalled and downloaded again since progress is supposed to be saved, went into the app again and I've lost all progress with teir 4. I'm back at Teir 3 with some gold now, but overall efforts to spend money to progress, along with time spent, has been wasted.