diff --git a/app/main/views/notifications.py b/app/main/views/notifications.py
index 7235a4b0b..fdde0f6bd 100644
--- a/app/main/views/notifications.py
+++ b/app/main/views/notifications.py
@@ -230,7 +230,7 @@ def view_letter_notification_as_preview(
     mimetype = 'image/png' if filetype == 'png' else 'application/pdf'
 
     return send_file(
-        filename_or_fp=file,
+        path_or_file=file,
         mimetype=mimetype,
     )
 
diff --git a/app/main/views/uploads.py b/app/main/views/uploads.py
index a3d43d7e2..d688e457f 100644
--- a/app/main/views/uploads.py
+++ b/app/main/views/uploads.py
@@ -584,7 +584,7 @@ def delete_contact_list(service_id, contact_list_id):
 def download_contact_list(service_id, contact_list_id):
     contact_list = ContactList.from_id(contact_list_id, service_id=service_id)
     return send_file(
-        filename_or_fp=BytesIO(contact_list.contents.encode('utf-8')),
+        path_or_file=BytesIO(contact_list.contents.encode('utf-8')),
         attachment_filename=contact_list.saved_file_name,
         as_attachment=True,
     )
diff --git a/app/s3_client/s3_mou_client.py b/app/s3_client/s3_mou_client.py
index d86e7b2cc..b6921df66 100644
--- a/app/s3_client/s3_mou_client.py
+++ b/app/s3_client/s3_mou_client.py
@@ -13,7 +13,7 @@ def get_mou(organisation_is_crown):
     try:
         key = get_s3_object(bucket, filename)
         return {
-            'filename_or_fp': key.get()['Body'],
+            'path_or_file': key.get()['Body'],
             'attachment_filename': attachment_filename,
             'as_attachment': True,
         }