How do I consume a ColdFusion webservice from C#?

I'm trying to use a webservice with the endpoint https://services.example.com/ASP_SecureWebServices.cfc?wsdl.

In the documentation I have this:

Request

<authorise>
  <site>xxx</site>
  <login>xxx</login>
  <password>xxx</password>
  <partnerid>xxx</partnerid>
  <wstype>xpt_exhibitors</wstype>
</authorise>

Authenticated Response

<authorisation>
  <service>getAuthToken</service>
  <authorised>OK</authorised>
  <authtoken>255461</authtoken>
</authorisation>

I’ve never used ColdFusion before, so I don’t understand how to make the request. Can anyone assist?

I’ve added a service reference like this:

But I don’t get this method: