Django smart selects is not working properly

Question

I try to chain four categories with django smart select but it does not work properly. Django does not take or input values from in the last one. clothing_size. It is working properly till clothing sizes. That selectbox is always empty. My model:

What could be the problem here? That does not seem like js problem, because other fields are working properly.

from django.db import models
from smart_selects.db_fields import ChainedForeignKey

# Create your models here.

class MainCategory(models.Model):
    name = models.CharField(max_length=20, null=True)

    def __str__(self):
        return self.name

class ClothingType(models.Model):
    main_category = models.ForeignKey(MainCategory, on_delete=models.CASCADE, null=True)
    clothing_type = models.CharField(max_length=64, null=True)

    def __str__(self):
        template = '{0.main_category} {0.clothing_type}'
        return template.format(self)

class ClothingSubType(models.Model):
    main_category = models.ForeignKey(MainCategory, on_delete=models.CASCADE, null=True)

    # clothing_type = models.ForeignKey(ClothingType, on_delete=models.CASCADE, null=True)
    clothing_type = ChainedForeignKey(ClothingType, chained_field="main_category", chained_model_field="main_category", show_all=False, auto_choose=True, sort=True, null=True)
    clothing_sub_type = models.CharField(max_length=254, null=True)

    def __str__(self):
        template = '{0.main_category} {0.clothing_type} {0.clothing_sub_type}'
        return template.format(self)
        
class ClothingSize(models.Model):
    main_category = models.ForeignKey(MainCategory, on_delete=models.CASCADE, null=True)
    clothing_type = ChainedForeignKey(ClothingType, chained_field="main_category", chained_model_field="main_category", show_all=False, auto_choose=True, sort=True, null=True)
    clothing_sub_type = ChainedForeignKey(ClothingSubType, chained_field="clothing_type", chained_model_field="clothing_type", show_all=False, auto_choose=True, sort=True, null=True)

    # clothing_sub_type = models.ForeignKey(ClothingSubType, on_delete=models.CASCADE, null=True)
    clothing_size = models.CharField(max_length=30, null=True)

    def __str__(self):
        template = '{0.main_category} {0.clothing_type} {0.clothing_sub_type} {0.clothing_size}'
        return template.format(self)

class Product(models.Model):
    name = models.CharField(max_length=30, null=True)
    sku = models.CharField(max_length=20, null=True)
    main_category = models.ForeignKey(MainCategory, on_delete=models.CASCADE, null=True)
    clothing_type = ChainedForeignKey(
                                        ClothingType, 
                                        chained_field="main_category", 
                                        chained_model_field="main_category", 
                                        show_all=False, 
                                        auto_choose=True, 
                                        sort=True, 
                                        null=True
                                        )
                                        
    product_category = ChainedForeignKey(
                                        ClothingSubType, 
                                        chained_field="clothing_type", 
                                        chained_model_field="clothing_type", 
                                        show_all=False,
                                        auto_choose=True, 
                                        sort=True, 
                                        null=True
                                        )

    clothing_size = ChainedForeignKey(
                                        ClothingSize,
                                        chained_field="clothing_sub_type",
                                        chained_model_field="clothing_sub_type",
                                        show_all=False,
                                        auto_choose=True, 
                                        sort=True, 
                                        null=True
                                        )

    def __str__(self):
        template = '{0.name}'
        return template.format(self)