Bouncie won't let me enter odometer reading

When I installed Bouncie, I did not enter the odometer information.  I'd like to enter it, but when I go into the vehicle information, the odometer field is not editable.  I can make changes to other fields (like, enter license plate number), but not the odometer.  I've read the help section about how to enter odometer mileage, and I'm sure I'm on the right screen.  Any other suggestions?