Consume REST webservice responses not getting suppressed

Hello,

We are having the REST consume webservice, where we are sending certain data from Peoplesoft to third party system as part of integration. But when we have a response code as 200, 404, 400 based on the various cases.

200 - OK

404 - If the ID not exists in third party system

400 - Bad request (if we send any blank data)

However, for 200 cases it is working fine and getting the proper responses and for 404 and 400 it is not getting the corresponding responses and it decides internally that is an error (it is not even consider as fault type - it is not satisfying the '.Isfault' function), How do we suppress the error/get these in fault types in terms of logging the responses? We have attached the document with messages for your reference.