Try using the steps below to navigate back to the area to change mileage expenses for a 1099-MISC on Schedule C.
To Edit your Vehicle Mileage:
1. Select "Business" at the top of the screen
2. Choose "Continue", then "I'll choose what
I work on"
3. Select "Start" next to "Business Income
and Expenses"
4. Select "Edit" next to your business name
5. Scroll down to Business Expenses
6. Now select "Start" next to "Business
Vehicle Expense"
7. Select "Edit" next to your vehicle
8. Continue until you arrive to the screen asking for mileage and
make any changes
For more information on claiming your mileage visit this link:
Business Use of Vehicles