You're still showing as super admin in that group. You won't be able to leave the group until you promote another premium member to be super admin as the group can't be left with no super admin at all. If the person you removed as super admin was a basic member, you won't be able to place him back unless he upgrades.
Sorry.
i wanted to quit a group which i was a super admins i quited from the main group and from the admins group so i made my self as a member to quit but i touched another member and he was a super admin now he is not a premium member he cannot be made as the super admins please fix the problem
http://www.chess.com/groups/home/th-admins