diff --git a/apps/pos_device/models.py b/apps/pos_device/models.py
index 6806e06..a3718d9 100644
--- a/apps/pos_device/models.py
+++ b/apps/pos_device/models.py
@@ -38,8 +38,50 @@ class Device(BaseModel):
 
 
 class DeviceVersion(BaseModel):
-    pass
+    device = models.ForeignKey(
+        Device,
+        on_delete=models.CASCADE,
+        related_name='devices',
+        null=True
+    )
+    company = models.ForeignKey(
+        PaymentCompany,
+        on_delete=models.CASCADE,
+        related_name='devices',
+        null=True
+    )
+    name = models.CharField(max_length=250, null=True)
+    code = models.IntegerField(default=0)
+    description = models.TextField(null=True)
+    enable = models.BooleanField(default=True)
+    remove = models.BooleanField(default=False)
+    
+    def __str__(self):
+        return f'Version: {self.name}-{self.device.serial}'
+    
+    def save(self, *args, **kwargs):
+        return super(DeviceVersion, self).save(*args, **kwargs)
 
 
 class Sessions(BaseModel):
-    pass
+    device = models.ForeignKey(
+        Device,
+        on_delete=models.CASCADE,
+        related_name='devices',
+        null=True
+    )
+    name = models.CharField(max_length=125, null=True)
+    password = models.CharField(max_length=25, null=True)
+    version = models.IntegerField(default=0)
+    mac = models.CharField(max_length=50, null=True)
+    ip = models.CharField(max_length=15, default='0.0.0.0')
+    sdk = models.TextField(null=True)
+    serial = models.TextField(null=True)
+    latitude = models.DecimalField(max_digits=20, decimal_places=10, null=True)
+    longitude = models.DecimalField(max_digits=20, decimal_places=10, null=True)
+    
+    def __str__(self):
+        return f'Session: {self.name}-{self.version}-{self.id}'
+    
+    def save(self, *args, **kwargs):
+        return super(Sessions, self).save(*args, **kwargs)
diff --git a/apps/product/web/api/v1/serializers/quota_serializers.py b/apps/product/web/api/v1/serializers/quota_serializers.py
index 8299aba..9da4623 100644
--- a/apps/product/web/api/v1/serializers/quota_serializers.py
+++ b/apps/product/web/api/v1/serializers/quota_serializers.py
@@ -50,7 +50,6 @@ class QuotaSerializer(serializers.ModelSerializer):
         instance.quota_weight = validated_data.get('quota_weight', instance.quota_weight)
         instance.remaining_weight = validated_data.get('remaining_weight', instance.remaining_weight)
         instance.quota_distributed = validated_data.get('quota_distributed', instance.quota_distributed)
-        instance.quota_balance = validated_data.get('quota_balance', instance.quota_balance)
         instance.product = validated_data.get('product', instance.product)
         instance.sale_type = validated_data.get('sale_type', instance.sale_type)
         instance.sale_unit = validated_data.get('sale_unit', instance.sale_type)