429 "prepayment credits are depleted" despite minimal usage — billing sync bug after Postpay→Prepay switch

Gemini API
1

Hello Google team,

My Gemini API project suddenly returns 429 RESOURCE_EXHAUSTED on every generateContent call, with the message “Your prepayment credits are depleted.” This started about a week ago and affects all my API keys at the same time.

Account / project details:

- Billing Account ID: 015AB8-C89A47-30D6..

- Project: Default Gemini Project (gen-lang-client-02490269..)

- Tier: Paid 1 (was upgraded to Tier 1 Postpay on June 2, 2026 via a $50 prepayment)

- Region/Country: Saudi Arabia (USD)

- Models tested: gemini-2.5-flash, gemini-2.0-flash, gemini-flash-latest — all fail with the same 429

What works:

- API key authenticates fine

- The project shows “Paid 1 · $250 Billing Account Tier Cap” in AI Studio

What fails:

- Every generateContent request returns: 429 RESOURCE_EXHAUSTED “Your prepayment credits are depleted”

The problem:

My total Gemini API usage since account creation is very low (the billing page itself shows I have NOT yet reached the “$100 spent” threshold). My Usage dashboard confirms only a tiny number of requests and tokens — nowhere near $50 of consumption. Yet my Credit balance shows $0.00 with no transaction history, and all keys stopped working simultaneously.

This exactly matches the Postpay->Prepay billing synchronization bug that many other users have reported in this same period. My account appears to have been silently switched from Postpay to Prepay, which zeroed my balance even though my real usage is minimal.

Request:

Please review the billing sync for billing account 015AB8-C89A47-30D6.. and project gen-lang-client-02490269.., restore the correct balance/quota, and let me know once the sync is fixed.

Thank you.

2

[UPDATE — additional finding]

After further investigation, I discovered that this issue is now connected to a second problem on my account:

My account has been restricted to generating only “AQ.” prefix API keys instead of the standard “AIza” format. This affects ALL projects, including new ones. The keys ending in …gxBA, …Yi8A, and …QO1A are all in the AQ. format.

When these AQ. keys are used against the generativelanguage.googleapis.com endpoint, combined with the quota on my paid project showing 0, every request fails with:

  • 429 RESOURCE_EXHAUSTED — “Your prepayment credits are depleted”

This exactly matches the automatic security restriction that many other developers have reported in this same period (there are numerous identical reports in this forum within the last few hours).

To confirm the problem is account-level and not code-level: a separate OLD key in the standard “AIza” format (from a different, free-tier project) still works correctly. Only my paid project’s keys — which were forced into the AQ. format — fail.

[Updated request]

  1. Please restore my account’s ability to generate standard “AIza” format API keys.
  2. Please review and restore the correct quota / prepaid balance for project gen-lang-client-02490269…

[Security assurance]
I keep all my API keys strictly private and server-side only (stored securely as environment secrets, never exposed in any client code or public repository). I am fully committed to all security best practices.

This is affecting a production service that serves real users, so I would be very grateful for your help in restoring normal access.

Thank you again for your time.


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