dom.getElementsByTagNameNS("urn:oasis:names:tc:SAML:1.0:assertion", 'Assertion')[0].toxml() IndexError: list index out of range

Question

We have used "Office365-REST-Python-Client 2.3.11" library to upload file on sharepoint. Suddenly code stopped working and started giving below issue.

code:

import json
from office365.runtime.auth.user_credential import UserCredential
from office365.runtime.http.request_options import RequestOptions
from office365.sharepoint.client_context import ClientContext
site_url = "https://{your-tenant-prefix}.sharepoint.com"
ctx = ClientContext(site_url).with_credentials(UserCredential("{username}", "{password}"))
request = RequestOptions("{0}/_api/web/".format(site_url))
response = ctx.execute_request_direct(request)
json = json.loads(response.content)
web_title = json['d']['Title']
print("Web title: {0}".format(web_title))

Error:

Traceback (most recent call last):
  File "test_upload.py", line 81, in <module>
    response = ctx.execute_request_direct(request)
  File "/home/ubuntu/atlas/national_kpi_table/venv/lib/python3.8/site-packages/office365/runtime/client_runtime_context.py", line 131, in execute_request_direct
    return self.pending_request().execute_request_direct(self._normalize_request(request))
  File "/home/ubuntu/atlas/national_kpi_table/venv/lib/python3.8/site-packages/office365/runtime/odata/odata_request.py", line 36, in execute_request_direct
    return super(ODataRequest, self).execute_request_direct(request)
  File "/home/ubuntu/atlas/national_kpi_table/venv/lib/python3.8/site-packages/office365/runtime/client_request.py", line 91, in execute_request_direct
    self.context.authenticate_request(request)
  File "/home/ubuntu/atlas/national_kpi_table/venv/lib/python3.8/site-packages/office365/sharepoint/client_context.py", line 230, in authenticate_request
    self._auth_context.authenticate_request(request)
  File "/home/ubuntu/atlas/national_kpi_table/venv/lib/python3.8/site-packages/office365/runtime/auth/authentication_context.py", line 89, in authenticate_request
    self._provider.authenticate_request(request)
  File "/home/ubuntu/atlas/national_kpi_table/venv/lib/python3.8/site-packages/office365/runtime/auth/providers/saml_token_provider.py", line 77, in authenticate_request
    self.ensure_authentication_cookie()
  File "/home/ubuntu/atlas/national_kpi_table/venv/lib/python3.8/site-packages/office365/runtime/auth/providers/saml_token_provider.py", line 84, in ensure_authentication_cookie
    self._cached_auth_cookies = self.get_authentication_cookie()
  File "/home/ubuntu/atlas/national_kpi_table/venv/lib/python3.8/site-packages/office365/runtime/auth/providers/saml_token_provider.py", line 97, in get_authentication_cookie
    token = self._acquire_service_token_from_adfs(user_realm.STSAuthUrl)
  File "/home/ubuntu/atlas/national_kpi_table/venv/lib/python3.8/site-packages/office365/runtime/auth/providers/saml_token_provider.py", line 140, in _acquire_service_token_from_adfs
    assertion_node = dom.getElementsByTagNameNS("urn:oasis:names:tc:SAML:1.0:assertion", 'Assertion')[0].toxml()
IndexError: list index out of range

Any help appreciated.