You can set the user's roles using the following example POST:
. . /api/v1/User/Roles
The user roles you want to set must be entered in the POST body.
When you set user roles, any user roles that were previously used and were not included
in the request are deselected. For example, an empty POST array removes all user roles.
For API calls that request to amend or get server data, the user must have the specific
roles added and activated by setting Selected to true.