Problem/Bug A problem regarding gamemode command for Admin

Hello there. I post this thread for I have a problem with my server regarding the usability of the gamemode command for the admins.

Therefore I have begun typing every permission node into the admin rank but when I login as an admin I cannot go into different gamemodes even though I have typed the essentials.gamemode permission node into the admin rank.

Really all I just want is for an Admin to be able to do everything an owner can do execpt banning and unbanning people and their IP addresses.

I use the Group Manager plugin to administrate my ranks. Also I have the basic plugins installed such as essentials, world edit and world guard.

I would like an admin to be able to use the /gamemode command but for some reason it doesn't work. And I have already gone through groups.yml and globalgroups.yml, but I cannot seem to find the problem.

The groups.yml and globalgroups.yml is attched as txt files.

I hope you guys can help me please. Therefore I hereby request your assistance
Many thanks in advance.