diff --git a/main.py b/main.py
index 87ea78f..c3d0684 100644
--- a/main.py
+++ b/main.py
@@ -32,7 +32,7 @@ def get_decoded_header(value):
     decoded_header_items = decode_header(value)
     decoded_header_value = ''
     for item in decoded_header_items:
-        decoded_item = item[0].decode(item[1]) if item[1] is not None else item[0]
+        decoded_item = item[0].decode(item[1], 'replace') if item[1] is not None else item[0]
         if isinstance(decoded_item, bytes):
             decoded_item = decoded_item.decode('ascii', 'replace')
         decoded_header_value += decoded_item