diff --git a/apps/api/src/services/telegram_gateway.py b/apps/api/src/services/telegram_gateway.py
index f547c4fe..f394758d 100644
--- a/apps/api/src/services/telegram_gateway.py
+++ b/apps/api/src/services/telegram_gateway.py
@@ -2683,6 +2683,13 @@ class TelegramGateway:
                 "namespace": (incident.signals[0].labels or {}).get("namespace", "") if incident.signals else "",
                 "error_type": (incident.signals[0].labels or {}).get("reason", (incident.signals[0].labels or {}).get("error_type", "")) if incident.signals else "",
             })
+
+            if freq is None:
+                await self.send_notification(
+                    f"📊 <b>事件歷史</b>\n\n🔖 <code>{html.escape(incident_id)}</code>\n\n⚠️ 無頻率統計資料"
+                )
+                return
+
             disposition = await counter.get_disposition_stats(anomaly_key)
 
             lines = [