Follow the below mentioned steps to delete a shared driver:

1) Select the car which you wish to delete the shared driver from.

2) Tap on the blue box titled "Shared driver(s)"

3) Click on the “Edit” button 

4) A red circle will appear next to all the shared drivers on the list

5) Tap on the red circle that corresponds to the driver you wish to delete.

6) You will be asked to confirm the removal. Please confirm by clicking “OK”. With this, you have successfully removed the shared driver.

*If you wish to restrict access to your car, you must delete the driver from the list.