Issue adding/updating device via api

I am trying to add or update devices to users via Node and a put request. Neither seem to work.

The response is an an empty object and I’m not seeing a 400, so I assume it think it’s working, but when looking at the person in customer there is no device.

Here is my code:

import { NextApiRequest, NextApiResponse } from "next";
import { TrackClient, RegionUS } from "customerio-node";
import Environment from "shared/utils/environment/environment";
import axios from "axios";

const analytics = new TrackClient(
  Environment.customerioSiteId,
  Environment.customerioApiKey,
  { region: RegionUS }
);

export default async function handler(
  req: NextApiRequest,
  res: NextApiResponse
) {
  const {
    userId,
    deviceId,
    lastUsed,
    deviceOS,
    deviceModel,
    appVersion,
    pushEnabled
  } = req.body;

  if (!userId) {
    res.status(400).json({ error: "userId is required" });
  }

  if (!deviceId) {
    res.status(400).json({ error: "deviceId is required" });
  }

  console.log("about to add Device");

  console.log("userId", userId);
  console.log("deviceId", deviceId);

  // const response = await analytics.addDevice(
  //   userId,
  //   deviceId,
  //   "ios"
  //   // {
  //   //   last_used: lastUsed,
  //   //   attributes: {
  //   //     device_os: deviceOS,
  //   //     device_model: deviceModel,
  //   //     app_version: appVersion,
  //   //     device_locale: deviceLocale,
  //   //     push_enabled: pushEnabled
  //   //   }
  //   // }
  // );

  const response = await axios.put(
    `https://track.customer.io/api/v1/customers/${userId}/devices`,
    {
      device: {
        id: deviceId,
        last_used: lastUsed,
        platform: "ios",
        attributes: {
          device_os: deviceOS,
          device_model: deviceModel,
          app_version: appVersion,
          push_enabled: pushEnabled
        }
      }
    },
    {
      headers: {
        "Content-Type": "application/json",
        Authorization: `Basic ${Buffer.from(
          `${Environment.customerioSiteId}:${Environment.customerioApiKey}`
        ).toString("base64")}`
      }
    }
  );

  console.log("response", response.data);

  res.status(200).json({ status: "ok" });
}

What am I missing?