Web APIs

We have used StartProcess() function in WEBAPI with Http method "POST", when we are testing it is giving response properly ,but if we are trying to call through expression rule using httpquery function ,it is throwing "HTTP/1.1 401 Unauthorized" error,
So we have created third party credentials after these setting also we are getting error "HTTP/1.1 404 Not Found".
Please help us to know the error or we are missing any configurations.

Please find below code snippet.
with(
a!startProcess(
processModel: cons!TEST_WEBAPI_PM,
processParameters: a!fromJson(
http!request.body
),
onSuccess: a!httpResponse(
statusCode: 200,
headers: {
a!httpHeader(name: "Content-Type", value: "application/json")
},
body: a!toJson(
fv!processInfo
)
),
onError: a!httpResponse(
statusCode: 500,
headers: {
a!httpHeader(name: "Content-Type", value: "application/json")...

OriginalPostID-242297