Persistent PREFILL_QUEUE_OVERLOADED errors on Gemini Flash

My Firebase project, SubstationAIPro, has been experiencing repeated Gemini Flash overload errors for the past several days.

The same circuit-analysis feature and similar circuit images were working normally before this issue started. I tested multiple different circuit images, and the requests are now repeatedly failing.

Firebase AI Monitoring shows errors including:

PREFILL_QUEUE_OVERLOADED
UNAVAILABLE
INTERNAL

The application shows:

“This model is currently experiencing high demand. Spikes in demand are usually temporary. Please try again later.”

I also tested different Gemini Flash models, including Gemini 3.8 Flash, but the same type of overload error occurred.

Could Google please investigate whether there has been any recent change in Gemini Flash backend capacity, regional capacity, routing, or service availability affecting this project?

Project: SubstationAIPro
Use case: Electrical substation circuit-diagram analysis using Gemini vision.

The feature worked reliably before this issue started. Please advise whether this is a service-side capacity issue or whether there is any project-specific problem that needs to be corrected.

I can provide Firebase AI Monitoring screenshots and error details if required.