How to whitelist people without restarting the server?

I have a server and I want to be able to add people to my whitelist from inside the server so that I dont have to restart the server though when I type in what I have to:

/whitelist add username_of_person_to_add

It just says that I dont have permission even though I am a level in the OP.json file

I have tried changing the level that I am an OP though it hasn't helped

Solution 1:

One thing you can do is type in console is "whitelist add username"

If you can not do that,

http://dev.bukkit.org/bukkit-plugins/permissionsex/

Create a group,

  Admin:
    default: false
    build: true
    permissions:
    - '*'

If you create a group set it to false If you want only certain people to have it or true if anyone can have it.

In console type "pex user add [USERNAME] group add Admin"

If you do not have that try /reload

Solution 2:

I managed to do it with the same code though in the gui