405 Client Error: Method Not Allowed when calling FedEx Web Services using Zeep in Python

Question

I'm attempting to integrate FedEx tracking services using Zeep in Python, but I'm encountering a "405 Client Error: Method Not Allowed" when I try to send a tracking request. I've been following FedEx's development guide and I've successfully used their WSDL in SoapUI. However, when I try to do the same with Zeep in my Python application, I hit this roadblock.

Here's the code snippet where the issue occurs:

from zeep import Client
from zeep.exceptions import Fault
from zeep.transports import Transport
from requests import Session
from requests.auth import HTTPBasicAuth

WSDL_URL = "https://wsbeta.fedex.com:443/web-services"

# authentication for the WSDL URL
session = Session()
session.auth = HTTPBasicAuth("USERNAME', 'PASSWORD') 

transport_with_basic_auth = Transport(session=session)

# Initialize the client with the FedEx WSDL URL
client = Client(WSDL_URL, transport=transport_with_basic_auth)

web_authentication_detail = {
    "UserCredential": {
        "Key": "---",
        "Password": "---"
    }
}

client_detail = {
    "AccountNumber": "---",
    "MeterNumber": "----"
}

tracking_number = "557----"  

#  a request dictionary
request_dict = {
    "WebAuthenticationDetail": web_authentication_detail,
    "ClientDetail": client_detail,
    "TransactionDetail": {
        "CustomerTransactionId": "Test Transaction"
    },
    "Version": {
        "ServiceId": "trck",
        "Major": 20,
        "Intermediate": 0,
        "Minor": 0
    },
    "SelectionDetails": {
        "CarrierCode": None,  
        "PackageIdentifier": {
            "Type": "TRACKING_NUMBER_OR_DOORTAG",
            "Value": tracking_number
        }
    }
}
try:
    # Send the tracking request
    response = client.service.track(**request_dict)
    print(response)
except Fault as e:
    print("Error:", e)

When I run the above code, I receive the following error:

requests.exceptions.HTTPError: 405 Client Error: Method Not Allowed for url: https://wsbeta.fedex.com:443/web-services

What I've tried so far:

Ensuring the URL is correct and accessible. Validating the WSDL with SoapUI, which works correctly. Checking that the credentials are correct.

What could be causing this issue, and how can I resolve it to successfully call the FedEx tracking service using Zeep?

Also, Please note that this is a test environment and not the live production system. I'm using test credentials and URLs as provided in the FedEx development documentation.