Update app.py

app.py

@@ -230,6 +230,9 @@ def predict():
                 df = pd.read_csv(filepath)
             else:
                 df = pd.read_excel(filepath)
+
+            # Replace blank/missing cells with "-"
+            df.fillna("-", inplace=True)
         except Exception as e:
             print(f'Error reading file: {e}', 'error')
             return redirect(url_for('index'))