RegisterConflictUsernameError

{
    "success": false,
    "errorCode": "CONFLICT",
    "message": "An account with this username already exists.",
    "error": "Conflict",
    "details": {
        "property1": {
            "code": "string",
            "message": "string"
        },
        "property2": {
            "code": "string",
            "message": "string"
        },
        "userName": {
            "code": "CONFLICT",
            "message": "Username is already taken."
        }
    }
}