YouTube Data API members.list returns 403 Forbidden despite proper OAuth scopes - How to enable? [closed]

I'm implementing YouTube channel membership verification and getting a 403 Forbidden error when calling the members.list endpoint, despite having proper OAuth credentials and scopes.My Setup:OAuth 2.0 with scopes: youtube.readonly and youtube.channel-memberships.creatorValid access token and refresh tokenChannel has memberships enabled and active membersAuthorization works fine for other YouTube API endpoints

Error:

GaxiosError: Access forbidden. The request may not be properly authorized.Status: 403Endpoint: https://youtube.googleapis.com/youtube/v3/members

API Call:

const response = await youtube.members.list({    auth: auth,    part: ["snippet"],    maxResults: 50});

Documentation says:

"This endpoint can only be used by individual creators to make requests for their own, channel-memberships-enabled YouTube channel. Reach out to your Google or YouTube representative to request access."

Question: What additional steps or permissions are required beyond OAuth scopes? Is there an API quota setting, project configuration, or application process I'm missing?