You can check your security by navigating to Manager > Config > Security > Edit Calculated Mileage.
Edit Via Driver Status:
To edit a driver's mileage via a driver's status, navigate to the Dispatch screen.
Select the driver you want to edit and click "Driver Status"
On the driver status screen, click on the "Total Mileage" link.
If you are using the "Google Maps" method of calculating mileage, you will see this screen, which shows the Google mileage estimate for each delivery run. You can edit the mileage by each order that is listed on the driver's status. Enter in the new mileage amount and click "Update".
The updated mileage amount will be displayed on the driver's status.
Tip: If you are using the "Ask Driver" method of calculating mileage; (found in config - employees) you will still be able to edit the driver mileage but it will be displayed differently. It will display the mileage the employee started with at the beginning of their shift and the final mileage when they complete their shift.
Edit Via Labor > Payroll Details Report:
You can also edit the mileage on the Payroll Details Report by clicking on the TR containing the mileage that you want to edit and clicking on the Total Mileage link.
Learn more by reading the Edit Driver Mileage On Payroll Details Report article.