ejabberd - How to set_room_affiliation for mod_muc in ejabberd?

Question

Hi am using ejabberd version 16.04 for my chat application and am using mod_rest for creating a muc room and for sending room invitation, now what i need is to set_room_affiliation for a particular mod_muc but its says error could some one help me out please...!!!

Below is the argument am passing for each respective ejabberd commands

Creating a Team

{"key": "secret","command": "create_room","args": ["kandan_team","conference","kandan.com"]}

Team got created. Passed...!!!

For sending Room Invitation to user 1

{"key": "secret","command": "send_direct_invitation","args": ["kandan_team","conference","none", "team_inviataion", "user1@kandan.com"]}

Inviatation sent successfully..!!! Passed..!!!

For sending Room Invitation to user 2

{"key": "secret","command": "send_direct_invitation","args": ["kandan_team","conference","none", "team_inviataion", "user2@kandan.com"]}

Inviatation sent successfully..!!! Passed..!!!

For removing user1 from team

{"key":"secret","command":"set_room_affiliation","args":["kandan_team", "conference", "user1@kandan.com", "outcast"]}

Couldn't remove user1 and saying as error..! Failed..!!!

Ejabberd.yml file configuration for mod_rest

 mod_restful:
 api:
  - path: ["admin"]
    module: mod_restful_admin
    params:
      key: "secret"
      allowed_commands: [register, unregister,status, add_rosteritem, create_room, send_direct_invitation, set_room_affiliation]
  - path: ["register"]
    module: mod_restful_register
    params:
      key: "secret"

So can someone help me out how to set_room_affiliation please ...!!!