Method Not Allowed when adding Group Members to a Group

API POST Request returns method_not_allowed

https://api.box.com/2.0/groups/group_memberships

The access token is valid and could add/update users or groups.

But unable to add a member to groups. Request body below

{
       "user": {
       "id": "12345"
       },
       "group": {
       "id": "12346"
       }
}

And the complete error response is

{"type":"error","status":405,"code":"method_not_allowed","help_url":"http:\/\/developers.box.com\/docs\/#errors","message":"Method Not Allowed","request_id":"e7r8jdhe2p6a2vn9"}

Not sure what's the issue here, the documentation doesn't say any prerequisites when adding group members.
App scopes "manage_managed_users manage_groups" should be enough, right?

Appreciate the help. Thanks in advance.

Comments