Change of cells settings after adding a new data to an existing Excel Worksheet

Question

I have the following code that appends a newly generated data to an already existing Excel Worksheet:

def save_data(data, filename, worksheet_name):
    try:
        # Load existing Excel file into a dictionary of DataFrames
        try:
            existing_data = pd.read_excel(filename, sheet_name=None)
        except FileNotFoundError:
            existing_data = {}
        
        # Check if the worksheet_name already exists
        if worksheet_name in existing_data:
            existing_data[worksheet_name] = pd.concat([existing_data[worksheet_name], data], ignore_index=True)
        else:
            existing_data[worksheet_name] = data
        
        # Write the combined data to Excel with multiple sheets
        while True:
            try:
                with pd.ExcelWriter(filename, engine='xlsxwriter') as writer:
                    for sheet_name, sheet_data in existing_data.items():
                        sheet_data.to_excel(writer, index=False, sheet_name=sheet_name)
                break
            except PermissionError:
                input('Dashboard open. Please close and press "Enter"')

        print(f"Data saved successfully to {filename} - Worksheet: {worksheet_name}")
    except Exception as e:
        print(f"An error occurred: {e}")

The data is appended succesfully, without overwriting an old data. However, the code changes the properties of the cells in the whole Workbook (the Workbook has few Worksheets) such as:

• date changes from short form into a longer form (with time)
• the width of the columns changes, so that one cannot see the whole text Even though I change it every time and save the changes, after conducting the save function, it always come back to, what I think, 'default settings'. How can I deal with it?

I haven not tried anything, as in my code there is nothing that suggests these changes. I expect the data to be succesfully appended, without changing other properties of the Worksheets.