Please help with WebClient

I am trying to debug php webclient code, see below.
I am sending in, or think I am sending in "Hello World"
What I get back is "No parameter came in" which is what the services function is designed to do. Spit out what you put in. See that code below.

It works fine when I call the service from a .net app but I cannot get it working in php, What am I doing wrong in my code below that it doesn't see the parameter I am sending in?

Code:

---

<?php
require_once('nusoaplib/nusoap.php');
$wsdl="http://MyImaginaryWebService.com/WebService.asmx?WSDL";
$client=new soapclient($wsdl);
   
              try{
                        $results = $client->__Call('GetMyParameter',array('pParameter'=>'Hello World'));
                        echo $results->GetMyParameterResult;

                  }
                  catch(Exception $e)
                  {
                  echo $e;
                  }                                     

?>

---

Code:

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<WebMethod()> _
      Public Function GetMyParameter(ByVal pParameter As String) As String

        If pParameter = "" Then
            pParameter = "No parameter came in"
        End If
        Return pParameter
    End Function

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