diff --git a/azbankgateways/default_settings.py b/azbankgateways/default_settings.py
index 72d5401..f0436dd 100755
--- a/azbankgateways/default_settings.py
+++ b/azbankgateways/default_settings.py
@@ -1,18 +1,10 @@
 """Default settings for messaging."""
 
-import django
 from django.conf import settings
 
 from azbankgateways.apps import AZIranianBankGatewaysConfig
 
-if django.__version__ >= "3.0":
-    from django.db import models
 
-    TEXT_CHOICES = models.TextChoices
-else:
-    from .models.enum_django import TextChoices
-
-    TEXT_CHOICES = TextChoices
 BANK_CLASS = getattr(
     settings,
     "CLASS",
@@ -24,7 +16,7 @@
         "ZIBAL": "azbankgateways.banks.Zibal",
         "BAHAMTA": "azbankgateways.banks.Bahamta",
         "MELLAT": "azbankgateways.banks.Mellat",
-	"PAYV1": "azbankgateways.banks.PayV1",
+        "PAYV1": "azbankgateways.banks.PayV1",
     },
 )
 _AZ_IRANIAN_BANK_GATEWAYS = getattr(settings, "AZ_IRANIAN_BANK_GATEWAYS", {})
@@ -39,16 +31,18 @@
 TRACKING_CODE_LENGTH = _AZ_IRANIAN_BANK_GATEWAYS.get("TRACKING_CODE_LENGTH", 16)
 IS_SAMPLE_FORM_ENABLE = _AZ_IRANIAN_BANK_GATEWAYS.get("IS_SAMPLE_FORM_ENABLE", False)
 IS_SAFE_GET_GATEWAY_PAYMENT = _AZ_IRANIAN_BANK_GATEWAYS.get("IS_SAFE_GET_GATEWAY_PAYMENT", False)
-CUSTOM_APP = _AZ_IRANIAN_BANK_GATEWAYS.get("CUSTOM_APP", None)
+CUSTOM_APP = _AZ_IRANIAN_BANK_GATEWAYS.get("CUSTOM_APP")
 if CUSTOM_APP:
     CALLBACK_NAMESPACE = f"{CUSTOM_APP}:{AZIranianBankGatewaysConfig.name}:callback"
     GO_TO_BANK_GATEWAY_NAMESPACE = f"{CUSTOM_APP}:{AZIranianBankGatewaysConfig.name}:go-to-bank-gateway"
     SAMPLE_RESULT_NAMESPACE = f"{CUSTOM_APP}:{AZIranianBankGatewaysConfig.name}:sample-result"
 else:
-    CALLBACK_NAMESPACE = _AZ_IRANIAN_BANK_GATEWAYS.get("CALLBACK_NAMESPACE", f"{AZIranianBankGatewaysConfig.name}:callback")
+    CALLBACK_NAMESPACE = _AZ_IRANIAN_BANK_GATEWAYS.get(
+        "CALLBACK_NAMESPACE", f"{AZIranianBankGatewaysConfig.name}:callback"
+    )
     GO_TO_BANK_GATEWAY_NAMESPACE = _AZ_IRANIAN_BANK_GATEWAYS.get(
         "GO_TO_BANK_GATEWAY_NAMESPACE", f"{AZIranianBankGatewaysConfig.name}:go-to-bank-gateway"
     )
     SAMPLE_RESULT_NAMESPACE = _AZ_IRANIAN_BANK_GATEWAYS.get(
         "SAMPLE_RESULT_NAMESPACE", f"{AZIranianBankGatewaysConfig.name}:sample-result"
-    )
\ No newline at end of file
+    )
diff --git a/azbankgateways/models/enum.py b/azbankgateways/models/enum.py
index e705a6a..ce0f1e5 100644
--- a/azbankgateways/models/enum.py
+++ b/azbankgateways/models/enum.py
@@ -1,9 +1,8 @@
+from django.db import models
 from django.utils.translation import gettext_lazy as _
 
-import azbankgateways.default_settings as settings
 
-
-class BankType(settings.TEXT_CHOICES):
+class BankType(models.TextChoices):
     BMI = "BMI", _("BMI")
     SEP = "SEP", _("SEP")
     ZARINPAL = "ZARINPAL", _("Zarinpal")
@@ -14,7 +13,7 @@ class BankType(settings.TEXT_CHOICES):
     PAYV1 = "PAYV1", _("PayV1")
 
 
-class CurrencyEnum(settings.TEXT_CHOICES):
+class CurrencyEnum(models.TextChoices):
     IRR = "IRR", _("Rial")
     IRT = "IRT", _("Toman")
 
@@ -27,7 +26,7 @@ def toman_to_rial(cls, amount):
         return amount * 10
 
 
-class PaymentStatus(settings.TEXT_CHOICES):
+class PaymentStatus(models.TextChoices):
     WAITING = "WAITING", _("Waiting")
     REDIRECT_TO_BANK = "REDIRECT_TO_BANK", _("Redirect to bank")
     RETURN_FROM_BANK = "RETURN_FROM_BANK", _("Return from bank")
diff --git a/azbankgateways/models/enum_django.py b/azbankgateways/models/enum_django.py
deleted file mode 100644
index e18f1ab..0000000
--- a/azbankgateways/models/enum_django.py
+++ /dev/null
@@ -1,77 +0,0 @@
-import enum
-
-from django.utils.functional import Promise
-
-
-class ChoicesMeta(enum.EnumMeta):
-    """A metaclass for creating a enum choices."""
-
-    def __new__(metacls, classname, bases, classdict):
-        labels = []
-        for key in classdict._member_names:
-            value = classdict[key]
-            if isinstance(value, (list, tuple)) and len(value) > 1 and isinstance(value[-1], (Promise, str)):
-                *value, label = value
-                value = tuple(value)
-            else:
-                label = key.replace("_", " ").title()
-            labels.append(label)
-            # Use dict.__setitem__() to suppress defenses against double
-            # assignment in enum's classdict.
-            dict.__setitem__(classdict, key, value)
-        cls = super().__new__(metacls, classname, bases, classdict)
-        cls._value2label_map_ = dict(zip(cls._value2member_map_, labels))
-        # Add a label property to instances of enum which uses the enum member
-        # that is passed in as "self" as the value to use when looking up the
-        # label in the choices.
-        cls.label = property(lambda self: cls._value2label_map_.get(self.value))
-        cls.do_not_call_in_templates = True
-        return enum.unique(cls)
-
-    def __contains__(cls, member):
-        if not isinstance(member, enum.Enum):
-            # Allow non-enums to match against member values.
-            return any(x.value == member for x in cls)
-        return super().__contains__(member)
-
-    @property
-    def names(cls):
-        empty = ["__empty__"] if hasattr(cls, "__empty__") else []
-        return empty + [member.name for member in cls]
-
-    @property
-    def choices(cls):
-        empty = [(None, cls.__empty__)] if hasattr(cls, "__empty__") else []
-        return empty + [(member.value, member.label) for member in cls]
-
-    @property
-    def labels(cls):
-        return [label for _, label in cls.choices]
-
-    @property
-    def values(cls):
-        return [value for value, _ in cls.choices]
-
-
-class Choices(enum.Enum, metaclass=ChoicesMeta):
-    """Class for creating enumerated choices."""
-
-    def __str__(self):
-        """
-        Use value when cast to str, so that Choices set as model instance
-        attributes are rendered as expected in templates and similar contexts.
-        """
-        return str(self.value)
-
-
-class IntegerChoices(int, Choices):
-    """Class for creating enumerated integer choices."""
-
-    pass
-
-
-class TextChoices(str, Choices):
-    """Class for creating enumerated string choices."""
-
-    def _generate_next_value_(name, start, count, last_values):
-        return name