diff --git a/bytetracker/byte_tracker.py b/bytetracker/byte_tracker.py
index 537d4d9..3a066e5 100644
--- a/bytetracker/byte_tracker.py
+++ b/bytetracker/byte_tracker.py
@@ -180,8 +180,8 @@ def __init__(self, track_thresh=0.45, track_buffer=25, match_thresh=0.8, frame_r
         self.max_time_lost = self.buffer_size
         self.kalman_filter = KalmanFilter()
 
-    def update(self, dets, _):
-        self.frame_id += 1
+    def update(self, dets, frame_id):
+        self.frame_id = frame_id
         activated_starcks = []
         refind_stracks = []
         lost_stracks = []