prevent deleting auto_created=True styles

apps/home/models.py

@@ -145,6 +145,12 @@ class MessageStyle(models.Model):
         verbose_name_plural = "message styles"
         get_latest_by = "id"
 
+    def delete(self, *args, **kwargs):
+        if self.auto_created:
+            raise ValidationError("Cannot delete 'MessageStyle' instance with 'auto_created=True'")
+
+        super().__init__(self)
+
     def __str__(self):
         return self.name