diff --git a/contrib/pyln-proto/pyln/proto/message/message.py b/contrib/pyln-proto/pyln/proto/message/message.py
index 1b8d8f37f..02af803f1 100644
--- a/contrib/pyln-proto/pyln/proto/message/message.py
+++ b/contrib/pyln-proto/pyln/proto/message/message.py
@@ -592,6 +592,7 @@ Returns None on EOF
             if fields[f.name] is None:
                 # optional fields are OK to be missing at end!
                 if f.option is not None:
+                    del fields[f.name]
                     break
                 raise ValueError('{}: truncated at field {}'
                                  .format(mtype, f.name))