For async tests and hooks, ensure "done()" is called; if returning a Promise, ensure it resolves

I have this test of nodejs when testing I get a error of done function not declared.

Error: Timeout of 2000ms exceeded. For async tests and hooks, ensure "done()" is called; if returning a Promise, ensure it resolves.

My test code is, I have the done call back but still getting the error to call the done();

    it('remove existing subdocument', (done) => {
    const Vic = new User({
      name: 'Vic',
      posts: [{ title: 'Leaning Nodejs' }]
    });

    vic.save()
      .then(() => User.findOne({ name: 'Vic' }))
      .then((user) => {
        const post = user.posts[0];
        post.remove();
        return user.save();
      })
      .then(() => User.findOne({ name: 'Vic' }))
      .then((user) => {
        assert(user.posts.length === 0);
        done();
      });
  });

via Gerald Brigen