Why returning more record when it should be one? Mongoose

Question

I'm getting more records returned when it should be one only. Right now I have only 2 records on the MongoDB attendance schema

Here is my schema:

const attendanceSchema = mongoose.Schema({
    WorkShopTitle: { type: String, trim: true }
    enrollment: [{
        studentUUID: { type: String, trim: true},
        studentName: { type: String, trim: true },
        }],
    Status:{type: String, default:"Open", trim: true}
}, { timestamps: true });

When I run this query:

const checkStudentEnrolled = await Attendance.findOne({"$and":[{_id:{"$eq": '6210834ce3a7b51ad5bde65e'}},{"enrollment.studentUUID":{"$eq":'6506de7b0d32492c878307a1992f54e8'}}]})

console.log(checkStudentEnrolled)

It returns both records John Doe and Mary Jane instead of John Doe only:

{
  _id: new ObjectId("6210834ce3a7b51ad5bde65e"),
  WorkShopTitle: 'Wellness',
  Status: 'Open',
  enrollment: [
    {
      studentUUID: '6506de7b0d32492c878307a1992f54e8',
      studentName: 'John Doe',
      _id: new ObjectId("6210846ffab50e051294c833"),
    },
    {
      studentUUID: 'f324e86498e64b6e858cf34b742c1899',
      studentName: 'Mary Jane',
      _id: new ObjectId("6210fe9022c55c1edeffe8c4"),
    }
  ],
  createdAt: 2022-02-19T05:42:36.946Z,
  updatedAt: 2022-02-23T06:09:31.911Z,
  __v: 0
}

How should I write the query to see only one return? Thanks

An update to this post:

I have found the solution and here is the final code:

const checkStudentEnrolled = await Attendance.findOne({"$and":[{_id:{"$eq": '6210834ce3a7b51ad5bde65e'}},{"enrollment.studentUUID":{"$eq":'6506de7b0d32492c878307a1992f54e8'}}]},{ 'enrollment.$': 1 })

But I'm not sure how does it work and hope someone here could explain this part in particular { 'enrollment.$': 1 }