diff --git a/src/pyOutlook/core/folder.py b/src/pyOutlook/core/folder.py
index af0238a..63538c6 100644
--- a/src/pyOutlook/core/folder.py
+++ b/src/pyOutlook/core/folder.py
@@ -86,7 +86,8 @@ def _json_to_folder(cls, account, json_value: dict) -> 'Folder':
         :rtype: Folder
         """
         from pyOutlook.services.folder import FolderService
-        return FolderService._json_to_folder(account, json_value)
+        service = FolderService(account)
+        return service._json_to_folder(json_value)
 
     @classmethod
     def _json_to_folders(cls, account, json_value: dict) -> list['Folder']:
@@ -105,7 +106,8 @@ def _json_to_folders(cls, account, json_value: dict) -> list['Folder']:
         :rtype: list[Folder]
         """
         from pyOutlook.services.folder import FolderService
-        return FolderService._json_to_folders(account, json_value)
+        service = FolderService(account)
+        return service._json_to_folders(json_value)
 
     def rename(self, new_folder_name: str) -> 'Folder':
         """Renames the folder to the provided name.
diff --git a/tests/core/test_folder.py b/tests/core/test_folder.py
index 1703f42..9f5b00b 100644
--- a/tests/core/test_folder.py
+++ b/tests/core/test_folder.py
@@ -80,11 +80,13 @@ def test_headers__with_different_token(self):
     def test_json_to_folder__delegates_to_folder_service(self, mock_folder_service):
         """Test that _json_to_folder delegates to FolderService"""
         mock_json = {'Id': 'test_id', 'DisplayName': 'Test'}
-        mock_folder_service._json_to_folder.return_value = self.test_folder
+        mock_service_instance = mock_folder_service.return_value
+        mock_service_instance._json_to_folder.return_value = self.test_folder
 
         result = Folder._json_to_folder(self.mock_account, mock_json)
 
-        mock_folder_service._json_to_folder.assert_called_once_with(self.mock_account, mock_json)
+        mock_folder_service.assert_called_once_with(self.mock_account)
+        mock_service_instance._json_to_folder.assert_called_once_with(mock_json)
         self.assertEqual(result, self.test_folder)
 
     @patch('pyOutlook.services.folder.FolderService')
@@ -92,11 +94,13 @@ def test_json_to_folders__delegates_to_folder_service(self, mock_folder_service)
         """Test that _json_to_folders delegates to FolderService"""
         mock_json = {'value': [{'Id': 'test_id', 'DisplayName': 'Test'}]}
         mock_folders = [self.test_folder]
-        mock_folder_service._json_to_folders.return_value = mock_folders
+        mock_service_instance = mock_folder_service.return_value
+        mock_service_instance._json_to_folders.return_value = mock_folders
 
         result = Folder._json_to_folders(self.mock_account, mock_json)
 
-        mock_folder_service._json_to_folders.assert_called_once_with(self.mock_account, mock_json)
+        mock_folder_service.assert_called_once_with(self.mock_account)
+        mock_service_instance._json_to_folders.assert_called_once_with(mock_json)
         self.assertEqual(result, mock_folders)
 
     @patch('pyOutlook.core.folder.requests.patch')