Unable to add tables in any location other than end of document

I have a Word docx with {{TABLE_PLACEHOLDER}} written in the text of the doc.

I would like to add a table in that location, but cannot manage to add a table anywhere else but at the end of the document.

Any help is appreciated.

import pandas as pd
from docx import Document

doc = Document('template_document.docx')

df = pd.DataFrame({
    'Column 1': [1, 2, 3],
    'Column 2': [4, 5, 6],
    'Column 3': [7, 8, 9]
})

table_data = df.values.tolist()

for p in doc.paragraphs:
    if '{{TABLE_PLACEHOLDER}}' in p.text:

        p.insert_paragraph_before()   ### THIS APPEARS TO DO NOTHING

        table = doc.add_table(rows=len(table_data)+1, cols=len(df.columns))
        
        for i, row in enumerate(table_data):
            for j, val in enumerate(row):
                cell = table.cell(i+1, j)
                cell.text = str(val)
        
        for j, header in enumerate(df.columns):
            cell = table.cell(0, j)
            cell.text = header

doc.save('output_document.docx')