f you are getting the error - 'We had a problem saving your mileage class. Please check the following: Class name already exists', then the most likely explanation is that the settings are configured only to view one type of mileage class. To address this an administrator will need to follow the steps below:
Go to Settings.
scroll part way down to the User Vehicles section.
Click the drop down for Vehicle Classes.
Select Both.
Then Save.