diff --git a/app.py b/app.py
index a5706ec..6d94fad 100644
--- a/app.py
+++ b/app.py
@@ -111,6 +111,7 @@ def extract(username: str, password: str):
         df = pd.read_html(historial_html_io)[0]
         
         if 'GRUPO' not in df.columns:
+           print(df.to_markdown(), file=sys.stderr)
            raise KeyError("Column 'GRUPO' not found in the DataFrame")
 
         # Convert the DataFrame to JSON