ClassCastException for SOAP API

Hi,

I am getting the ClassCastException for SOAP API, please can some one help me to resolve the issue.

I am using Katalon 6.

com.kms.katalon.core.webservice.exception.WebServiceException: java.lang.ClassCastException: javax.wsdl.extensions.UnknownExtensibilityElement cannot be cast to javax.wsdl.extensions.soap.SOAPOperation
at com.kms.katalon.core.webservice.common.SoapClient.parseWsdl(SoapClient.java:111)
at com.kms.katalon.core.webservice.common.SoapClient.send(SoapClient.java:170)
at com.kms.katalon.controller.WebServiceController.sendRequest(WebServiceController.java:113)
at com.kms.katalon.composer.webservice.parts.SoapServicePart$4.run(SoapServicePart.java:235)
at org.eclipse.jface.operation.ModalContext$ModalContextThread.run(ModalContext.java:119)
Caused by: java.lang.ClassCastException: javax.wsdl.extensions.UnknownExtensibilityElement cannot be cast to javax.wsdl.extensions.soap.SOAPOperation
at com.kms.katalon.core.webservice.common.SoapClient.parseService(SoapClient.java:145)
at com.kms.katalon.core.webservice.common.SoapClient.lookForService(SoapClient.java:125)
at com.kms.katalon.core.webservice.common.SoapClient.parseWsdl(SoapClient.java:109)
… 4 more

Thank you,
Vinay