403 PERMISSION_DENIED "project denied access", Quota Tier Unavailable on new free-tier project, models.list returns 200

Gemini API
,
1

Environment:

  • Personal Gmail account (not Workspace)
  • Country: India
  • No billing account attached
  • Project ID: newp-5044..
  • Project Number: 5928029166..
  • API key: newly created from AI Studio (AQ. auth key format)
  • Generative Language API: enabled and confirmed

What works:

  • GET /v1beta/models returns HTTP 200 with the full model list

What fails:

  • POST /v1beta/models/gemini-2.5-flash:generateContent returns:
    HTTP 403 PERMISSION_DENIED
    “Your project has been denied access. Please contact support.”

AI Studio shows Quota Tier: Unavailable for this project.

I have already tried: creating brand-new projects, creating new API keys,
and creating the project in Cloud Console first and importing it into
AI Studio. The tier remains Unavailable in every case.

Since models.list succeeds with the same key, this appears to be an
account-level flag rather than a key, quota, or API-enablement issue.
Requesting manual review, suspected false-positive.

2

Hello @Itachi_Uchiha2 ,

Getting a 403 API error response and / or seeing “Unavailable” next to your project in AI audio indicates a flag has been placed on your account. To proceed:

  1. If you’re on the free tier with no billing attached, you should consider setting up billing. In most cases this is enough to clear any flag on your account. Please note this will mean you lose your free tier quota. You should also see a banner in AI studio prompting you to set up billing.

  2. If you are on a paid tier, check for banners / error callouts in the AI Studio Projects page & the Billing page. Mostly these flags cause visible banners or other errors on these pages with concrete next steps / appeal links. You can also check the email address associated with your project for information on next steps.

3

Yeah, I’ve heard of it if I setup billing flags will be cleared, but I want to use the free tier one, I’ve only used api keys for the development of my personal app and I just tested it on my machine, I don’t know why my account is flagged.