PDF to CSV: not able to extract always properly first row of a table

[aborruso]

Hi,
I have this input PDF.

In page 1 I have more than one rows, in page 2 only one.

I built this sample script to extract these tables (these are two pages of a 100-page PDF).

import sys
import os

sys.path.insert(0, os.path.expanduser("~/.local/lib/python3.11/site-packages"))

import fitz  # PyMuPDF
import pandas as pd

def extract_tables_from_pdf(pdf_path, output_folder):
    doc = fitz.open(pdf_path)
    
    for page_num in range(len(doc)):
        page = doc.load_page(page_num)
        tables = page.find_tables()

        for table_num, table in enumerate(tables):
            df = table.to_pandas()
            csv_output_path = os.path.join(output_folder, f"page{page_num + 1}_table{table_num + 1}.csv")
            df.to_csv(csv_output_path, index=False)
            print(f"Table {table_num + 1} from {page_num + 1} extracted and saved in {csv_output_path}")

    doc.close()

pdf_path = "file.pdf"
output_folder = "."  

try:
    extract_tables_from_pdf(pdf_path, output_folder)
    print(f"Extraction completed. Tables were saved in {output_folder}")
except Exception as e:
    print(f"An error occurred during the extraction of the tables: {str(e)}")

When it extracts the tables from page 1, I have the header:

N. Prog,N. Parz.,N. Foglio,N. Particella,Estensione Incendio
1696,801,38,3636,Parziale
1697,802,38,3637,Parziale
1698,803,38,3730,Totale

When it extracts the tables from page 2, I have no header:

1734,1,24,17,Parziale

Here my CSV output.

What's wrong in my code? Why does it behave differently on the two pages? Why is having a single row table a problem?

Thank you