If you need to edit a recommendation request you've submitted, you can do so from your user activity page. While you can only edit your recommender's name and email address from this page, once your recommender accesses the form they will be able to edit all of their contact information. You can edit your recommender's email address or name from here:
A new email is automatically sent when you edit the email address. Please note that you cannot change the information of a recommender who has already started or submitted their letter of recommendation. If your recommender has started the form but will not be completing it, please have him/her contact us directly at email@example.com to request that the form be reset.
The information you edit will only update on your activity page, and any changes made here will not be reflected in the application itself. This is normal system behavior.