[Urgent] Gemini API Billing Issue: Unexpected Charges for Unused Models (Tier 1)

Gemini API
1

Hello Gemini API Team and Developer Community,

I am a Paid Tier 1 user facing a critical billing issue that has resulted in a massive spike in my API costs. I am reaching out for immediate assistance and investigation regarding unauthorized model usage appearing on my bill.

1. Project Context:

  • Account Tier: Paid Tier 1.

  • Models Used: My project code explicitly calls only gemini-2.5-pro and gemini-2.5-flash.

  • Cost Spike: I am observing a sharp and disproportionate increase in expenses that far exceeds the expected budget based on my actual traffic.

2. The Issue: Billing for “Foreign” Models: According to the billing breakdown in the Google Cloud Console, a significant portion of my costs is attributed to the following models, which my project NEVER requests:

  • imagen-4.0-generate (Image generation model)

  • gemini-3-pro

  • gemini-3-pro-image

  • gemini-2.5-flash-preview-image

Billing
Billing1962×1213 124 KB

Questions for the Google AI Team:

  1. Why is my project—which strictly calls gemini-2.5-pro and gemini-2.5-flash—incurring charges for imagen-4.0-generate, gemini-3-pro, and others?

  2. What mechanism triggers these requests? Is there a known issue with automatic fallback, redirection, or incorrect billing labeling?

  3. How can I access detailed logs/reports for these specific SKUs to verify the origin of these requests?

  4. Will Google consider a refund for these unexpected and unauthorized charges?

:light_bulb: Note to the Community: If anyone else has noticed charges for models they don’t use (especially multimodal ones like imagen-4.0-generate or image-specific Gemini versions), please share your experience below.

I request the Gemini API and Google Cloud Billing teams to conduct an urgent investigation. It is impossible to maintain development and budget planning with such unpredictable billing behavior.

Thank you.