diff --git a/src/services/watchProgress.js b/src/services/watchProgress.js
index 0e7cf0a..3d5e2aa 100644
--- a/src/services/watchProgress.js
+++ b/src/services/watchProgress.js
@@ -5,8 +5,9 @@ const REPORT_INTERVAL_MS = 10000;
 const lastReportedAt = new Map();
 
 export function reportWatchProgress(episodeId, positionSeconds, durationSeconds, source = 'web', force = false) {
-  const id = Number(episodeId);
-  if (!Number.isFinite(id) || id <= 0) return;
+  // 剧集 ID 为 19 位长整型，超出 JS 安全整数范围，必须保持字符串，禁止 Number 转换
+  const id = String(episodeId ?? '');
+  if (!/^\d+$/.test(id)) return;
   const now = Date.now();
   if (!force && now - (lastReportedAt.get(id) || 0) < REPORT_INTERVAL_MS) return;
   lastReportedAt.set(id, now);