While users can update their own profile, an Admin can manually update any User's profile. That being said, we do not recommend making changes to any fields that are updated nightly through the API as the API will update those fields back to what they previously were. These simple steps will help you to change/update any of your user's profile.
Navigate to Admin > Users
Search the user for whom you wish to edit the profile and click Edit
Edit the field in the necessary field and click Save
Please contact email@example.com with any questions.