Type in the windows search bar ''Regedit'' and press enter.
Expand the ''HKEY_USERS'', then expand the 'S-1-5-21-2912689050-646343581-1041484845-1001'' (there might be different for you, and u may also have 2 of these.
Expand both of them and u should see ''SOFTWARE'' at only one of those 2.
Continue by expanding ''SOFTWARE'' and then look for ''KITKA GAMES''.
Expand it, click on ''STUMBLE GUYS'' then on the right, right click ''FREE_NAME_CHANGE, then click ''MODIFY'' and change the value data from 0 to 1. (u have to do this everytime u want a new free name change.)
HOPE THIS HELPED <3
Link to my tutorial posted on youtube if u didn't understand still : https://www.youtube.com/watch?v=2vWuhARh6WI