Loopback 4: Query the relation model

Question

I am new to Loop Back, but I want to use it for my upcoming API application. I am currently testing the features it has to offer, but I'm stuck on doing an advance query on a sub model of my root entity. I apologize in advance if this is already answered, but I've spent hours searching the web for answers and have not gotten anywhere. Furthermore, I saw below on LB4 website, but for unknown reasons it's not working for me.

customerRepo.find({
  include: [
    {
      relation: 'orders',
      scope: {
        where: {name: 'ToysRUs'},
        include: [{relation: 'manufacturers'}],
      },
    },
  ],
});

I am essentially using two models - User and Note where User has many Notes. I used LB4 CLI 99.9% of times to create the datasource, models, repositories and relations. I have even added inclusion resolver to my note repository as below.

this.registerInclusionResolver('user', this.user.inclusionResolver);

However, when I try to run below filter against my note repository, it does not apply the where filter against User. Oddly, when I add the scope block, the user is no longer included in the response.

{
    "limit": 5,
    "include": [
        {
            "relation": "user",
            "scope": {
                "where": {
                    "username": "jdoe@example.com"
                }
            }
        }
    ]
}

My project is a boilerplate code created using lb4 app command. I've then added my datasource, models, repositories, and controllers.

Any help will be greatly appreciated.