How can I add data from a subscheme to my mongodb database ?

See more:

MongoDB

Typescript

Backend
Hey, I have this bandscheme in mongo:

BandSchema = new Schema({
    name: String,
    genre: String,
    cdlist:
    [{
        cd: Cd
    }]
},
{
    timestamps: true
});

this cd scheme:

const CdSchema = new Schema({
    madeinyear: String,
    madeincountry: String,
    name: String,
    image: String,
    songs:
    [{
        // Deze lijst gaat dus song objecten bevatten.
        song: Song
    }]
});

Frontend
And this is what I a trying to do in angular/typescript

import {Band} from '../shared/models/band.model';
import {Cd} from '../shared/models/cd.model';
//import {nummer} from '../shared/models/nummer.model';
import {BandsService} from '../shared/services/band.service';
import {FormControl, FormGroup, Validators} from '@angular/forms';
import {ActivatedRoute} from '@angular/router';
import {Component, Input, OnInit} from '@angular/core';

@Component({
  selector: 'app-addEdit-band',
  templateUrl: './addEdit-band.component.html',
  styleUrls: ['./addEdit-band.component.css']
})
export class addEditBandComponent implements OnInit {
  clickMessage = '';
  cds: Cd[] = new Array<Cd>();
  id: number;
  constructor(private bandsService: BandsService) { }

  ngOnInit() {
  }

  onAddCdClick(cd:string) {
    if (cd) {
      this.cds.push({'name': cd});
    }
  }


  addBand(name, genre) {
      console.log(name,genre);
      //const nummer = new Nummer();
      const band = new Band({ 'name': name,
         'genre': genre , 'cdlist': this.cds
        ]
      console.log('band', band);
      this.bandsService.addBand(band);
  }
}

The problem here is it wont add the cd name to the array, even tho it does add 2 objects to the database(2 empty objects with an _id).

What I have tried:

I have tried it on alot of different ways.