diff --git a/app/modules/dump/wotwizard/wotwizard.dump.ts b/app/modules/dump/wotwizard/wotwizard.dump.ts
index 35ce2cf4fdef6c38767df176c9eaee8fe315750b..f6df40e4366b33e2006205be99ba49167a3b7b12 100644
--- a/app/modules/dump/wotwizard/wotwizard.dump.ts
+++ b/app/modules/dump/wotwizard/wotwizard.dump.ts
@@ -53,6 +53,6 @@ export async function dumpWotWizard(server: Server) {
       Directory.GET_FILE_PATH(WotWizardConstants.DB_NAME_0),
       Directory.GET_FILE_PATH(WotWizardConstants.DB_NAME)
     );
-    fs.writeFileSync(updatingFile, Date.now());
+    fs.writeFileSync(updatingFile, String(Date.now()));
   }
 }