diff --git a/src/ossfs/file.py b/src/ossfs/file.py
index 12954e8..a3aede7 100644
--- a/src/ossfs/file.py
+++ b/src/ossfs/file.py
@@ -30,7 +30,7 @@ def _upload_chunk(self, final: bool = False) -> bool:
             This is the last block, so should complete file, if
             self.autocommit is True.
         """
-        self.loc = self.fs.append_object(self.path, self.loc, self.buffer.getvalue())
+        self.loc = self.fs.append_object(self.path, self.offset, self.buffer.getvalue())
         return True
 
     def _initiate_upload(self):