diff --git a/dictation_server/src/gateways/adb2c/adb2c.service.ts b/dictation_server/src/gateways/adb2c/adb2c.service.ts
index 088b847..1a81390 100644
--- a/dictation_server/src/gateways/adb2c/adb2c.service.ts
+++ b/dictation_server/src/gateways/adb2c/adb2c.service.ts
@@ -40,6 +40,7 @@ export class AdB2cService {
     const authProvider = new TokenCredentialAuthenticationProvider(credential, {
       scopes: ['https://graph.microsoft.com/.default'],
     });
+
     this.graphClient = Client.initWithMiddleware({ authProvider });
   }
 
@@ -143,21 +144,15 @@ export class AdB2cService {
    * @param externalId ユーザ情報
    * @param password パスワード
    */
-  async changePassword(
-    externalId: string,
-    password: string,
-  ): Promise<{ sub: string }> {
+  async changePassword(externalId: string, password: string): Promise<void> {
     this.logger.log(`[IN] ${this.changePassword.name}`);
     try {
       // ADB2Cのユーザのパスワードを変更する
-      const changeUser = await this.graphClient
-        .api(`/users/${externalId}`)
-        .patch({
-          passwordProfile: {
-            password: password,
-          },
-        });
-      return { sub: changeUser.id };
+      await this.graphClient.api(`/users/${externalId}`).patch({
+        passwordProfile: {
+          password: password,
+        },
+      });
     } catch (e) {
       this.logger.error(e);
       throw e;