diff --git a/internal/task/polling_handler.go b/internal/task/polling_handler.go
index 4c59b50..fb24d97 100644
--- a/internal/task/polling_handler.go
+++ b/internal/task/polling_handler.go
@@ -266,7 +266,8 @@ func (h *PollingHandler) HandleCarddataCheck(ctx context.Context, t *asynq.Task)
 
 	// 更新 Redis 缓存
 	h.updateCardCache(ctx, uint(cardID), map[string]any{
-		"current_month_usage_mb": updates["current_month_usage_mb"],
+		"current_month_usage_mb":  updates["current_month_usage_mb"],
+		"last_gateway_reading_mb": gatewayFlowMB,
 	})
 
 	// 任务 18.3: 调用 UsageService.DeductDataUsage 进行流量扣减