I am trying to retrieve the total number of users registered each month grouping them by year and month they registered in MongoDB My user model looks like this

email: String,
  
  gender: String,
  
  password: {
    hash: {
      type: String,
      // required: true
    },
    salt: {
      type: String,
      // required: true
    },
    reset: {
      id: {
        type: String,
        default: "",
      },
      code: {
        type: String,
        default: "",
      },
    },
  },
  name: {
    first: String,
    last: String,
    username: String,
  },
  date: {
    registered: {
      type: Date,
    }
  }

The date parameter is an ISO string

the query that I tried is this

var today = new Date();


            data.newUsersEachMonth=await AccountModel.aggregate([
                { "$match": {
                    "date": {"date.registered": { "$lt": today.toISOString() }}
                    }},
                { "$group": {
                        "_id": {
                            "year": { "$year": "$date" },
                            "month": { "$month": "$date" },
                        },
                        "count": { "$sum": 1 }
                    }}
            ])

But it returns an empty array How can i solve this?

UPDATE

As suggested i tried these two queries

                { "$match": {
                    "date.registered": { "$lt": today.toISOString() }
                    }},
                { "$group": {
                        "_id": {
                            "year": { "$year": "$date.registered" },
                            "month": { "$month": "$date.registered" },
                        },
                        "count": { "$sum": 1 }
                    }}
            ])

and

data.newUsersEachMonth=await AccountModel.aggregate([
                { "$match": {
                    "date.registered": { "$lt": today.toISOString() }
                    }},
                { "$group": {
                        "_id": {
                            "year": { "$year": "$date" },
                            "month": { "$month": "$date" },
                        },
                        "count": { "$sum": 1 }
                    }}
            ])```

Still getting an empty array