If you want to edit anything about an already created vehicle such as resetting the mileage back to 0 or changing which branch the vehicle comes under just follow the steps below;
1) To find the vehicle in question you will need to go to the vehicles section. The tab for it can be found on the portals task bar at the top of the screen.
2) You are now looking at the vehicles screen, here you will see all your vehicles and information about them such as make, model, their current mileage etc. To find the vehicle you want to change just click on the Add Filter box above it and type in the vehicle registration.
3) Once you found the vehicle you are after you should see on the far right side 2 options a Cog Wheel and a Cross clicking on the cross will delete the vehicle but to edit the details you will want to click on the Cog Wheel. Once you do that you should be looking at a screen like this.
4) Here is where you edit the details. The only thing you are not allowed to edit is the vehicle registration but you are now able to edit any other detail of it such as the mileage and the branch which can be seen below as all you need to do is click on branch, select the new one and then select save.
And that would be it. Once you've changed any of the details such putting the mileage back to 0 or changing the branch and hitting save the vehicle will have now had its details changed to anything you edited.