diff --git a/pyrogram/client.py b/pyrogram/client.py
index 68afabf6..5c95296a 100644
--- a/pyrogram/client.py
+++ b/pyrogram/client.py
@@ -880,7 +880,7 @@ class Client(Methods, Scaffold):
                 local_id=file_id.local_id,
                 big=file_id.thumbnail_source == ThumbnailSource.CHAT_PHOTO_BIG
             )
-        elif file_type in (FileType.THUMBNAIL, FileType.PHOTO):
+        elif file_type == FileType.PHOTO:
             location = raw.types.InputPhotoFileLocation(
                 id=file_id.media_id,
                 access_hash=file_id.access_hash,
@@ -892,7 +892,7 @@ class Client(Methods, Scaffold):
                 id=file_id.media_id,
                 access_hash=file_id.access_hash,
                 file_reference=file_id.file_reference,
-                thumb_size=""
+                thumb_size=file_id.thumbnail_size
             )
 
         limit = 1024 * 1024
diff --git a/pyrogram/file_id.py b/pyrogram/file_id.py
index 8bca0edd..c91c6431 100644
--- a/pyrogram/file_id.py
+++ b/pyrogram/file_id.py
@@ -166,7 +166,7 @@ class FileId:
         volume_id: int = None,
         thumbnail_source: ThumbnailSource = None,
         thumbnail_file_type: FileType = None,
-        thumbnail_size: str = None,
+        thumbnail_size: str = "",
         secret: int = None,
         local_id: int = None,
         chat_id: int = None,