Invalid OAuth token error

API
4

Did you exchange the returned ?code for an access token as per step 3?

3) On your server, get an access token by making this request:

POST https://id.twitch.tv/oauth2/token
    ?client_id=<your client ID>
    &client_secret=<your client secret>
    &code=<authorization code received above>
    &grant_type=authorization_code
    &redirect_uri=<your registered redirect URI>
Here is a sample request:

POST https://id.twitch.tv/oauth2/token
    ?client_id=uo6dggojyb8d6soh92zknwmi5ej1q2
    &client_secret=nyo51xcdrerl8z9m56w9w6wg
    &code=394a8bc98028f39660e53025de824134fb46313
    &grant_type=authorization_code
    &redirect_uri=http://localhost

On the docs Dist Linked?