diff --git a/tools/ndnsec/cert-gen.cpp b/tools/ndnsec/cert-gen.cpp
index cc77f02..c151471 100644
--- a/tools/ndnsec/cert-gen.cpp
+++ b/tools/ndnsec/cert-gen.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2013-2022 Regents of the University of California.
+ * Copyright (c) 2013-2023 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
  *
@@ -100,8 +100,8 @@
     additionalDescription.set(key, value);
   }
 
-  time::system_clock::TimePoint notBefore;
-  time::system_clock::TimePoint notAfter;
+  time::system_clock::time_point notBefore;
+  time::system_clock::time_point notAfter;
 
   if (vm.count("not-before") == 0) {
     notBefore = time::system_clock::now();