Issue Activating OpenAI API Billing – Payment Method Declined

Hello everyone,

I’m currently trying to activate billing for the OpenAI API so I can start using it in my Python applications (via LiteLLM). However, I’m facing an issue where all my payment methods are being declined during the billing setup process.

Here are the details of my situation:

• I attempted to add multiple payment methods (credit/debit cards).

• Each attempt results in a “payment declined” message.

• I verified that:

  • The cards are active and have sufficient balance.

  • International/online transactions are enabled.

  • Billing address details are entered correctly.

• I am based in Oman, and I’m not sure if there are regional restrictions affecting this.

Because of this, I’m unable to proceed and keep getting this error when running my code:

“You exceeded your current quota… insufficient_quota”

I would really appreciate guidance on:

1. Are there any country-specific restrictions for API billing?

2. Are there recommended payment methods that work reliably?

3. Could this be related to bank-side blocking or OpenAI-side validation?

4. Is there an alternative way to activate billing (e.g., prepaid credits, different setup)?

Any help or similar experiences would be greatly appreciated.

Thank you in advance!