Plugin Help Help with groupmanager.

Hi, I am trying to develop my own prison server with a bunch of friends but now im stuck at a problem with groupmanager, several ranks have taken over the permissions from other ranks : C has taken over permissions from D D from E E from F etc. untill P I dont know how it got this way and I have no idea how to undo this any help would really be appreciated! Ty already for taking the time to read this.