You said API is working in ReadyAPI.
If it is SOAP, then I don't expect it work in Swagger as it deals with REST services.
In general, you can go to the raw tab and ensure all the data and header and authentication, if applicable, is supplied in Postman. By the way, Postman mostly used for REST, and you should check if it supports for SOAP messages.
For Postman specific issues, the appropriate forum should be approached.
Yes, it supports SOAP API. For your information, the first, second, and third APIs work fine. However, there is an issue with the fourth API. For example, when we send the request for the first API, we receive a token. We then pass this token in the second step, and again in the third step. However, in the fourth step, an issue arises. can you check this video please.
