Update app.py

app.py

@@ -74,7 +74,9 @@ def select_nearest_items(df):
     nearest_items = pd.DataFrame()
     for _, row in df_sorted.iterrows():
         if row['Marketplace'] not in included_marketplaces:
-            nearest_items = pd.concat([nearest_items, row], ignore_index=True)
+            # Convert row to DataFrame and append correctly
+            row_df = pd.DataFrame([row])
+            nearest_items = pd.concat([nearest_items, row_df], ignore_index=True)
             included_marketplaces.add(row['Marketplace'])
         if len(included_marketplaces) >= 3:  # Ensure at least 3 unique marketplaces are included
             break