OneLogin_Saml2_Error: Redirect to invalid URL: null

[ovidner]

https://app.getsentry.com/liubiljettse/production/issues/99983253/

OneLogin_Saml2_Error: Redirect to invalid URL: null
(8 additional frame(s) were not displayed)
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  File "newrelic/hooks/framework_django.py", line 872, in wrapper
    return wrapped(*args, **kwargs)
  File "django/views/generic/base.py", line 89, in dispatch
    return handler(request, *args, **kwargs)
  File "saml_service_provider/views.py", line 39, in post
    return HttpResponseRedirect(auth.redirect_to(req['post_data']['RelayState']))
  File "onelogin/saml2/auth.py", line 181, in redirect_to
    return OneLogin_Saml2_Utils.redirect(url, parameters, request_data=self.__request_data)
  File "onelogin/saml2/utils.py", line 217, in redirect
    OneLogin_Saml2_Error.REDIRECT_INVALID_URL