Prejudiced in terms of racial sterio type

Called Old mutual to confirm the payout date for a policy and was advised to get a consent letter from my wife as I'm not the policy holder. I requested to speak to a team leader and request if I could conference my wife on the other line for her to give consent. She agreed and conferenced the call to my wife. She was asked to confirm her details. She confirmed her details and the team leader then said she is not my wife on the other end of the line. she then said she will get a Xhosa speaking agent to speak to her. Then a Xhosa speaking agent spoke to my wife and my wife responded in English as per usual. The agent confirms her details and she says that the profile for my wife says she only speaks Zulu. My wife confirms that she cannot speak Zulu properly as she is a Sesotho speaking African lady. My wife confirms she can speak English, Sesotho and Afrikaans well but Zulu was not her strong point. What makes me angry is that my wife is supposed to sound black as she has a black surname? so if she was White lady married to a Zulu man them would this be a problem. Now we where told that they will call us back as they realized it was a black lady speaking like a white women.