Mongoose virtual populate with match

when i'm trying to make a virtual populate and make a match inside, it returns TypeError: Cannot read property '_id' of undefined

const userSchema = mongoose.Schema(
    channelName: {
      type: String,
      required: [true, 'Please add a channel name'],
      unique: true,
      uniqueCaseInsensitive: true
  { toJSON: { virtuals: true }, toObject: { virtuals: true }, timestamps: true }

userSchema.virtual('subscribers', {
  ref: 'Subscription',
  localField: '_id',
  foreignField: 'channelId',
  justOne: false,
  count: true,
  options: {
    match: { subscriberId: this._id }
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