Same way as springfield clearly explained. Just change the searched value type as "string", and then put the nickname in, it will search and it will show you the search results on the left side. double click all of those same names, not only 1 result, and write the new name and overwrite it. It will already update the ingame values. So you will see it changing after alt + tab.
By the way it could be better if you could stop spitting everything else inside the "CLEO requests", this thing, has nothing. to do. with cleo.