I have a contact entry with no first name and a last name of "Charles Schwab Customer Service". When I tell Siri "Call Charles Schwab Customer Service", it shows the words on the screen exactly as I've spoken them, so it clearly understands what I've said. But instead of calling the contact, it asks, "Call Jones Communication Customer Service on 336 Post Office Rd...?" Obviously, Siri doesn't connect what it knows I'm saying to the contact entry I want it to call.
What do I need to do to get Siri to make the call I want it to make?