Hello Navin,
I can read that you do not have any Communication Arrangement for your web service in the system.
This is the issue I think.
The communication arrangement is what allows a certain technical user to consume the API. As soon as you are playing with web service, you need a communication arrangement from my experience.
Without it, you won't be able to access the endpoint.
So first step, create the corresponding Communication system + Communication scenario.
From this scenario (it might already exists as a standard scenario), create the Communicatoin Arrangement.
For the security, choose Basic Auithenticaiton and set the technical user/password who will be used to consume the API.
When the Communication arrangement has ben created, redownload WSDL for your API and import it in SOAP UI. Add a Basic Authentication to your Request in SOAP UI. Fill the user/password you created in the COmmunicatoin Arrangement.
It should work.
Have a great one.
Jacques-Antoine