OAuth Configuraton in AEM

We have configured our instances with SSO SAML configuration.

Authentication is working fine with SSO Azure Sign in.

But when a third party consumes our pages or ajax calls to fetch some internal data, they are getting 401 Un Authorized,

As a tenant we have created an APP with client id, secret and mentioned scope. With this third party is able to generate token. But when they use token, they are getting 401.

Is it something like, we have to configure OAuth as well for third party token authorization ?

Please suggest