I want to share what is working for me. I'm using Python 3.12.1

from pptx import Presentation
import pathlib
import datetime
template=pathlib.Path(r'C:\Template.pptx')
outputfile=pathlib.Path(r'C:\Output.pptx')
params={#your_keys_&_values
        }


def search_and_replace(input, output,**kwargs):
    """"search and replace text in PowerPoint while preserving formatting"""
    prs = Presentation(input)
    for slide in prs.slides:
        for shape in slide.shapes:
            for key, value in kwargs.items():         
                if not shape.has_text_frame:
                    continue
                for paragraph in shape.text_frame.paragraphs:
                    for run in paragraph.runs:
                        if key in run.text:
                            run.text=run.text.replace(key,value)
                if shape.has_table:
                        for row in shape.table.rows:
                            for cell in row.cells:
                                paras = cell.text_frame.paragraphs
                                for para in paras:
                                    for run in para.runs:
                                        if key in run.text:
                                            new_text = run.text.replace(str(key), str(value))
                                            fn = run.font.name
                                            fz = run.font.size 
                                            run.text = new_text
                                            run.font.name = fn
                                            run.font.size = fz
    prs.save(output)

search_and_replace(template,outputfile,**params)