Update retriever.py

retriever.py

@@ -311,10 +311,10 @@ Do not include explanations, steps, justifications, or additional text.
        try:
         import pandas as pd
         df = pd.read_excel(file_path)
-            for col in df.columns:
-               if df[col].dtype == object: 
-                  return df[col].dropna().astype(str).tolist()
-           return []
+        for col in df.columns:
+            if df[col].dtype == object: 
+                return df[col].dropna().astype(str).tolist()
+            return []
        except Exception as e:
            logger.error(f"Error extracting from Excel: {e}")
            return []