First and foremost, make sure that the files Fuel_Log.csv and Vehicles.csv are present in the 'Fuel Buddy' folder on Google Drive. If you have service reminders, then the Services.csv file should also be present. Next, try to delete all the existing vehicles in the app prior to restoring data. If you still see an error, then share you data with email@example.com. We'll have a look at what the issue could be.