Permission For Donator

Hello Everyone
I had a problem again,

so, I've been wearing - pocketmine.command.gamemode permissions for my donor group
but, it does not work
and how to use other permissions not only for ops? but donor can use too

I use xPermission 1.3.1
solution please guys
and recomended plugin for group or manage permission

Try using PurePermission, it haven't got any problems with a group

here :
https://github.com/PurePlugins/PurePerms

use a permission manager, in this case you can use PurePerms :3