Changing a google drive file label value via API Python

I've been trying to modify the label value of a file using the following code.

However, it's not working. Do you have any ideas?

# Import Libraries 

    import os
    from google.oauth2.credentials import Credentials
    from google_auth_oauthlib.flow import InstalledAppFlow
    from googleapiclient.discovery import build
    from googleapiclient.errors import HttpError

# Define the required scopes
SCOPES = ['https://www.googleapis.com/auth/drive', 'https://www.googleapis.com/auth/drive.labels']

# Authenticate and load credentials
def authenticate():
    creds = None
    # The file token.json stores the user's access and refresh tokens.
    if os.path.exists('token.json'):
        creds = Credentials.from_authorized_user_file('token.json', SCOPES)
    
    # If there are no valid credentials available, let the user log in.
    if not creds or not creds.valid:
        if creds and creds.expired and creds.refresh_token:
            creds.refresh(Request())
        else:
            flow = InstalledAppFlow.from_client_secrets_file(
                'credentials.json', SCOPES)  # Use the correct file name here
            creds = flow.run_local_server(port=0)
        # Save the credentials for the next run
        with open('token.json', 'w') as token:
            token.write(creds.to_json())
    return creds


# Main function to update the label on a file
def update_label(file_id, label_id, public_choice_id):
    creds = authenticate()
    service = build('drive', 'v3', credentials=creds)

    try:
        # Get the file's metadata including labels
        file_metadata = service.files().get(fileId=file_id, fields='id,labels').execute()

        # Get the existing labels
        labels = file_metadata.get('labels', [])

        # Update the label for 'Data Classification' to 'Public'
        for label in labels:
            if label['id'] == label_id:
                label['value'] = public_choice_id  # Set the label value to "Public"

        # Update the file with the new labels
        updated_file_metadata = service.files().update(
            fileId=file_id,
            body={'labels': labels}
        ).execute()

        print(f"Label for file {file_id} updated successfully!")

    except HttpError as error:
        print(f"An error occurred: {error}")

# Example usage
file_id = '1pXX6SPbHuEJeO8wI8LIACbfEEItIzRIz'  # The ID of the file you want to modify
label_id = 'A9438FD180'  # Data Classification label ID
public_choice_id = '66645FBAAC'  # Public choice ID for the label

update_label(file_id, label_id, public_choice_id)

What I’ve tried: I’ve confirmed that the file has labels applied and the file_id is correct. I’ve made sure that the required scopes are set, including https://www.googleapis.com/auth/drive and https://www.googleapis.com/auth/drive.labels. I’ve also tried refreshing the token.json and re-authorizing the credentials, but the issue persists.

I also failed retrieving the current label and value label from the file

from googleapiclient.discovery import build
from google_auth_oauthlib.flow import InstalledAppFlow

# SCOPES needed to access labels
SCOPES = ['https://www.googleapis.com/auth/drive', 'https://www.googleapis.com/auth/drive.labels']

# Authenticate and create the API client
flow = InstalledAppFlow.from_client_secrets_file(
    'credentials.json', SCOPES)
creds = flow.run_local_server(port=0)

# Build the Drive API client
service = build('drive', 'v3', credentials=creds)

# Build the Labels API client
labels_service = build('drive', 'v3', credentials=creds)

# Fetch the labels for the file
file_labels = labels_service.files().get(fileId=file_id, fields='id,labels').execute()

# Check the labels associated with the file
print("File Labels:", file_labels)

But I get this message:

HttpError: <HttpError 400 when requesting https://www.googleapis.com/drive/v3/files/1pXX6SPbHuEJeO8wI8LIACbfEEItIzRIz?fields=id%2Clabels&alt=json returned "Invalid field selection labels". Details: "[{'message': 'Invalid field selection labels', 'domain': 'global', 'reason': 'invalidParameter', 'location': 'fields', 'locationType': 'parameter'}]"

Why am I receiving this error when trying to get the file metadata with labels? How can I fix this issue to successfully modify the label value for a file? Thanks in advance for your help!