OAuthCode for Application Server RESTFul APIs

We have a requirement to expose One Identity REST APIs to external application to read/write user data. After going through REST API document, i came to know about default authentication module which is DialogUser, but we prefer to user OAuth.

I have managed to enable and install RSTS service on windows server but somehow i'm getting "invalid request" in the authorization code text field after successful authentication.

Request:

https://<Hostname>/RSTS/Login?response_type=code&client_id=urn:OneIdentityManager/Web&redirect_uri=urn:InstalledApplication&state=bhgghgku756565tghjg

Would appreciate any help on this?