Feing response data different With other tools

Question

I am attempting to make a request through Feign, but when I send a request to the same endpoint using Postman or Python's requests library, I get different results. What could be the reason for this?

#Avi Client
@FeignClient(name="aviAPI", url="${avi.url}", configuration=AviAPIConfig.class)
 public interface AviAPIClient {

    @GetMapping(value="/api/virtualservice")
    JSONObject getVirtualService(@RequestParam(value = "name",required = false) String name);

}

#Result
...
            "vrf_context_ref": "data",
            "vsvip_ref": "data",
            "weight": 1
}

python3 or postman result

            "vip" : [{
                     .... data
             }],

            "vrf_context_ref": "data",
            "vsvip_ref": "data",
            "weight": 1

I expect the same result when I send a request using Postman or Python.