I am getting an error when I try to do a webservice callout to cvent.  I am using the SOAP1.1 wsdl

11:31:10.147 (1147039000)|EXCEPTION_THROWN|[877]|System.CalloutException: Web service callout failed: Unable to parse callout response. Apex type not found for element http://schemas.cvent.com/api/2006-11=LoginResult
11:31:10.147 (1147193000)|METHOD_EXIT|[18]|01pW00000008dg0|apiCventCom200611.V200611Soap.Login(String, String, String)
11:31:10.147 (1147211000)|CONSTRUCTOR_EXIT|[1]|01pW00000008di6|<init>()
11:31:10.147 (1147280000)|FATAL_ERROR|System.CalloutException: Web service callout failed: Unable to parse callout response. Apex type not found for element http://schemas.cvent.com/api/2006-11=LoginResult

public apiCventCom200611.V200611Soap cv = new apiCventCom200611.V200611Soap();
    
    public ImportUserSurvey() {
         schemasCventComApi200611.LoginResult LoginResult = cv.Login(account, username, password);
        
         //assign login object to session
          cv.CventSessionHeaderValue = new cv.CventSessionHeader();
          cv.CventSessionHeaderValue.CventSessionValue = loginResult.CventSessionHeader;