This week's book giveaways are in the Cloud and AI/ML forums. We're giving away four copies each of Cloud Native Patterns and Natural Language Processing and have the authors on-line! See this thread and this one for details.
Your portType seems to be in namespace http://customer.services.ws.m2m.airtel.com which is defined in the wsdl:import part. You've only shown the xsd but not the wsdl... How does it look like? Also how do you code your client?