Ban User returns, 'Missing required parameter "user_id"'

API
2 
const body = {
    "user_id": "9876", //test user
    "duration": 30,
    "reason": "no reason"
}

Should be

const body = {
    data: {
        "user_id": "9876", //test user
        "duration": 30,
        "reason": "no reason"
    }
}