diff --git a/src/identity-challenge/challenge-email.cpp b/src/identity-challenge/challenge-email.cpp
index a439807..4e2e249 100644
--- a/src/identity-challenge/challenge-email.cpp
+++ b/src/identity-challenge/challenge-email.cpp
@@ -170,5 +170,5 @@
   return;
 }
 
-}  // namespace ndncert
-}  // namespace ndn
+} // namespace ndncert
+} // namespace ndn