Gemini Ultra daily limit reached after only a few hours while API quotas remain unused

Hello Google AI Studio team,

I believe I may have encountered an issue with AI Studio usage limits, and I would appreciate your help verifying whether this is expected behavior or a bug.

Environment

  • Google AI Ultra subscription (active)
  • Google AI Studio
  • Heavy coding workflow using AI Studio
  • Project: MY BRAIN AI
  • Google Cloud billing enabled
  • Gemini API enabled

What happened

Yesterday I upgraded to Google AI Ultra.

Yesterday’s daily limit was reached, which I expected.

Today the daily limits reset successfully.

I started working again at approximately 14:00.

After only about 4 hours of development, AI Studio stopped working and displayed:

“You’ve reached your limit for the day.”

At the same time, another message appeared:

“Encountered retriable error from model provider: Agent execution terminated due to error.”

Why this seems incorrect

I checked multiple places before opening this topic.

Google Cloud

  • Billing is active.
  • No quota exhaustion is visible.

Gemini API Rate Limits

For my project:

  • RPM usage is not exhausted.
  • TPM usage is not exhausted.
  • RPD usage is not exhausted.

The rate limit dashboard still shows available capacity.

Google Cloud APIs

No API quota errors are reported.

My question

Could someone please clarify:

  1. Which specific limit is being reached?
  2. Is this an AI Studio conversation limit?
  3. Is this an Agent/Flow execution limit?
  4. Is this related to Gemini Ultra?
  5. Could this be a temporary backend issue?

At the moment, the message says I have reached the daily limit, but all visible API quotas appear to have remaining capacity.

If needed, I can also provide:

  • screenshots of the error,
  • Gemini API Rate Limit pages,
  • Google Cloud quota pages,
  • project configuration.

Thank you very much for your help.