diff --git a/Qiita-2018/OtpSample/packages.config b/Qiita-2018/OtpSample/packages.config
index 5762754..882ea14 100644
--- a/Qiita-2018/OtpSample/packages.config
+++ b/Qiita-2018/OtpSample/packages.config
@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="Newtonsoft.Json" version="11.0.2" targetFramework="net461" />
+  <package id="Newtonsoft.Json" version="13.0.2" targetFramework="net461" />
 </packages>
\ No newline at end of file