diff --git a/packages/backend/src/i18n.ts b/packages/backend/src/i18n.ts
index 25d5cf4..ab945dd 100644
--- a/packages/backend/src/i18n.ts
+++ b/packages/backend/src/i18n.ts
@@ -5,6 +5,9 @@ import fs from 'fs';
 
 // --- 动态确定支持的语言 ---
 const localesDir = path.join(__dirname, 'locales');
+// --- 添加调试日志 ---
+console.log(`[i18next-debug] Calculated locales directory path: ${localesDir}`);
+// --- 结束调试日志 ---
 let dynamicSupportedLngs: string[] = [];
 try {
   const entries = fs.readdirSync(localesDir, { withFileTypes: true });
diff --git a/packages/backend/src/services/notification.service.ts b/packages/backend/src/services/notification.service.ts
index a0ab41e..b39b40e 100644
--- a/packages/backend/src/services/notification.service.ts
+++ b/packages/backend/src/services/notification.service.ts
@@ -12,7 +12,7 @@ import {
 } from '../types/notification.types';
 import * as nodemailer from 'nodemailer';
 import Mail from 'nodemailer/lib/mailer';
-import i18next, { defaultLng, supportedLngs } from '../i18n';
+import i18next, { defaultLng, supportedLngs } from '../i18n'; // Import supportedLngs
 import { settingsService } from './settings.service';
 
 
@@ -274,6 +274,9 @@ export class NotificationService {
             // --- 添加调试日志 ---
             console.log(`[通知调试] 刚从数据库获取的 langSetting: ${langSetting}`);
             // --- 结束调试日志 ---
+            // --- 添加调试日志 ---
+            console.log(`[通知调试] Checking langSetting against supportedLngs:`, supportedLngs);
+            // --- 结束调试日志 ---
             if (langSetting && supportedLngs.includes(langSetting)) {
                 userLang = langSetting;
             }