diff --git a/CHANGELOG.md b/CHANGELOG.md
index a8976e0e91..6e34067658 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,14 +1,7 @@
 ## Unreleased
 
-### General
--
-
 ### Client
--
-
-### Server
--
-
+- Fix: キャッシュを削除しないとクライアントが使用できないことがある問題を修正
 
 ## 2025.6.2
 
diff --git a/packages/frontend-shared/js/i18n.ts b/packages/frontend-shared/js/i18n.ts
index db06ad7f42..25581b969a 100644
--- a/packages/frontend-shared/js/i18n.ts
+++ b/packages/frontend-shared/js/i18n.ts
@@ -72,7 +72,7 @@ export class I18n<T extends ILocale> {
 
 					console.error(`Unexpected locale key: ${String(p)}`);
 
-					return p;
+					return new Proxy({} as any, new Handler<TTarget[keyof TTarget] & ILocale>());
 				}
 			}
 
@@ -141,7 +141,7 @@ export class I18n<T extends ILocale> {
 
 					console.error(`Unexpected locale key: ${String(p)}`);
 
-					return p;
+					return new Proxy((() => p) as any, new Handler<TTarget[keyof TTarget] & ILocale>());
 				}
 			}