Gemini API returns 429 RESOURCE_EXHAUSTED despite Tier 1 quota showing almost no usage

Hi Google Gemini API Team,

I am integrating the Gemini API into an internal business application for extracting structured trip/booking information from screenshots.

My Google AI Studio project is on Tier 1 paid billing.

Project ID: sanjar-e-infosync

The AI Studio Rate Limit page shows that my usage is far below the available quota. For example, the dashboard shows approximately:

  • RPM: 2 / 1K
  • TPM: 1.65K / 2M
  • RPD: 4 / 10K

However, API requests are consistently returning:

HTTP 429

RESOURCE_EXHAUSTED

I also tested a very small text-only generateContent request directly, without sending any screenshots or large payload, and it also returned:

429 Too Many Requests

This suggests the problem is not caused by the size of my application request.

The API key belongs to the same Google AI Studio / Google Cloud project, and paid billing has already been activated. AI Studio shows the project as Tier 1.

The model currently being tested is:

gemini-3.7-flash

Could you please advise why RESOURCE_EXHAUSTED is being returned when the displayed RPM, TPM and RPD quotas have not been exhausted?

Is there another project-level, model-level, billing activation, regional, or account quota that could be causing this 429?

I would also appreciate guidance on how to identify the specific quota responsible for the RESOURCE_EXHAUSTED response when the API response does not provide a quota violation or retry-after value.

Thank you.
With Regards
Sanjar Tranzways