From time to time, you might need to edit end-users. This traditionally will fall into one of 2 categories:
From time to time, end-users will open multiple accounts for their various email addresses. This can lead to a lot of confusion, so it is often best to merge them into one another. To do this, open all the user pages in question. Then locat the User ID of the primary one (it can be found in the URL). Using this, go to the various user account pages and click the arrow next to the "New Ticket" button. In the dropdown, select "Merge into another user". A modal will then appear, asking for the User ID to merge the user into. Input the User ID of the primary account, then click the "Merge" button. It will then show you what it will do. Once you are sure this is correct, click the "Confirm and merge" button.

This traditonally will stem from a Shared Organization request. The process for doing this is exactly the same as a Shared Organization request, except you make the changes on the User page. See Shared Organizations for more details.