How to test errors with Chai?

I am testing an api route that fetches an user. It works well. Now, I want to test if the route throws an error with the right message if I fetch an user that doesn't exist. The test claims to be positive, but I know it's not because I can't console.log the result nor the error in the .end() callback. here is the test and the route:

require("dotenv").config();
import chai from "chai";
import chaiHttp from "chai-http";
import connectToDatabase from "../database/connection";
import { app } from "../index";
import jwt from "jsonwebtoken";

chai.use(chaiHttp);
const api = chai.request(app);

before((done) => {
  connectToDatabase().then(() => done());
});

const token = jwt.sign(
  { _id: "123", locale: "en" },
  process.env.JWT_TOKEN_KEY,
  {
    expiresIn: "14d",
  }
);

describe("GET /user/:id", () => {
  it("return user information", () => {
    api
      .get("/user/607183db2020190b510bd9a5")
      .set("Cookie", `mycookie=${token};`)
      .end((err, res) => {
        chai.expect(res).to.have.status(200);
        chai.expect(res.body.user._id).to.equal("607183db2020190b510bd9a5");
      });
  });
  it("throws an error if the user doesn't exist", () => {
    api
      .get("/user/abc")
      .set("Cookie", `mycookie=${token};`)
      .end((err, res) => {
        console.log("res failed ok", res, "eeror", err); // this line never shows up
        chai.expect(err).to.throw("error.unknown");
      });
  });
});



// the route:
const getUser = async (
  req: GetUser,
  res: IResponse
): Promise<IResponse> => {
  try {
    const user = await UserControler.findUserById(req.params.id);
    return res.status(200).json({ user });
  } catch (err) {
    throw new Error("error.unknown");
  }
};

export default getUser;

How to fix this?