Find Child by field in Mongoose

I am trying to filter data with below JSON, but it not filters data. It gives some error and when I am trying to add array brackets from starting and ending element then error appears go away but still it also not filter data. Can anyone help me on this ?

Mongoose schema that i want to search in

{
    "TotalRecords": 10,
    "TotalNumberOfPages": 2,
    "CurrentPageIndex": 0,
    "PageSize": 5,
    "Result": [
        {
            "_id": "62dd88e570f781ae1482d85a",
            "CreatedOn": "2022-07-05T00:00:00.000Z",
            "ModifiedBy": {
                "_id": "62934444557dbf5b693efa72",
                "FirstName": "Rohit",
                "LastName": "Patel"
            },
            "ModifiedOn": "2022-07-05",
            "IsDelete": "0",
            "CreatedBy": {       
                "_id": "62934444557dbf5b693efa72",
                "FirstName": "Rohit",
                "LastName": "Patel"
            },
            "SizeName": "S"
        },
          {
            "_id": "62f9436216c64494dbb16c4a",
            "SizeName": "Test6",
            "CreatedBy": {
                "_id": "62934444557dbf5b693efa72",
                "FirstName": "Maulik",
                "LastName": "Patel"
            },
            "CreatedOn": "2022-07-05T00:00:00.000Z",
            "IsDelete": "0",
            "ModifiedBy": {
                "_id": "62934444557dbf5b693efa72",
                "FirstName": "Maulik",
                "LastName": "Patel"
            },
            "ModifiedOn": "2022-07-06"
        }
    ]
}

Mongoose Query to filter 

db.collection.find({ 
      'Result.CreatedBy.FirstName':{
                                   $eq: "Rohit"                    
                                }  
    });```