fix

src/customer/models.py

@@ -801,26 +801,32 @@ class Payment(models.Model):
         payment = super(Payment, self).save(*args, **kwargs)
         return payment
 
-    def confirmed_purchase(self, **kwargs):
-        try:
-            self.status = self.SUCCESS
-            self.date = datetime.now().date()
-            self.save()
-        except Payment.DoesNotExist:
-            log.info(f"payment with id={kwargs['InvId']} not found")
+
+def confirmed_purchase(**kwargs):
+    try:
+        payment = Payment.objects.get(
+            pk=kwargs['InvId'],
+            order_amount=kwargs['OutSum']
+        )
+        payment.status = Payment.SUCCESS
+        payment.date = datetime.now().date()
+        payment.save()
+
+    except Payment.DoesNotExist:
+        log.info(f"payment with id={kwargs['InvId']} not found")
 
 
 # Robokassa
 @receiver(result_received)
 def order_completed(sender, **kwargs):
-    sender.confirmed_purchase(sender, **kwargs)
+    confirmed_purchase(**kwargs)
 
 
 # Robokassa for local debugging
 @receiver(success_page_visited)
 def success_page_visited_completed(sender, **kwargs):
     if settings.DEBUG:
-        sender.confirmed_purchase(sender, **kwargs)
+        confirmed_purchase(**kwargs)
 
 
 @receiver(post_save, sender=Payment)