1. To edit a courier, you have to be first on your operator account.
2. Press on the Courier tab from the left side of the page.
3. Then press on the List tab from below in order to see all couriers.
4. Then press on the Edit button on the right of the wanted courier.
5. Here you can modify the wanted fields. After modifying the fields, press on the Update button in order for the changes to take effect.