diff --git a/af_benchmark/benchmark.py b/af_benchmark/benchmark.py
index a788569..e6ae084 100644
--- a/af_benchmark/benchmark.py
+++ b/af_benchmark/benchmark.py
@@ -111,7 +111,7 @@ def update_report(self):
         )
 
         # Add custom labels
-        for label, value in custom_labels.items():
+        for label, value in self.custom_labels.items():
             if label not in report:
                 report[label] = value