diff --git a/src/detail/challenge-encoder.hpp b/src/detail/challenge-encoder.hpp
index 0bd930c..f5cad6f 100644
--- a/src/detail/challenge-encoder.hpp
+++ b/src/detail/challenge-encoder.hpp
@@ -34,7 +34,7 @@
 void
 decodeDataContent(const Block& contentBlock, requester::RequestState& state);
 
-} // namespace ChallengeEncoder
+} // namespace challengetlv
 } // namespace ndncert
 } // namespace ndn