One of the parameter values from the list is not being used

I am performing a sweep but one of the of the value has not been explored even once after 30+ runs. The entire config is given below but the main part is the pool_type parameter.

  pool_type:
    values:
      - cls
      - mean
      - sum

Only the values mean and sum have been used so far. Another photo attached shows that (I have grouped them by pool type and only two show up)

early_terminate:
  min_iter: 3
  type: hyperband
method: bayes
metric:
  goal: maximize
  name: precision
name: kinase_VEGFR2_sweep_full
parameters:
  batch_size:
    values:
      - 16
      - 32
      - 64
  drop_prob:
    distribution: uniform
    max: 0.5
    min: 0.1
  epochs:
    value: 100
  hidden_size1:
    values:
      - 128
      - 256
      - 512
  hidden_size2:
    values:
      - 32
      - 64
      - 128
      - 256
  loss:
    values:
      - bce
  lr:
    distribution: uniform
    max: 0.001
    min: 1e-05
  model:
    values:
      - thaonguyen217/farm_molecular_representation
      - ibm/MoLFormer-XL-both-10pct
      - seyonec/PubChem10M_SMILES_BPE_450k
      - DeepChem/ChemBERTa-10M-MLM
      - DeepChem/ChemBERTa-77M-MLM
      - DeepChem/ChemBERTa-10M-MTR
      - DeepChem/ChemBERTa-77M-MTR
  pool_type:
    values:
      - cls
      - mean
      - sum
  weight_decay:
    distribution: uniform
    max: 0.01
    min: 1e-07