If a payment fails, do not start by buying gift cards or a new virtual card. First identify the merchant, product and account you are paying for. A ChatGPT subscription, OpenAI API usage, a Claude plan and Claude Console credits are different purchases.
Avoid the most expensive mix-up
OpenAI bills Codex API-key use through the API account rather than included ChatGPT plan usage. Anthropic also separates Claude subscriptions from its API. Check the active account and login method before a large coding job; a successful subscription payment does not prove the job will use it.
Claude Code has a particularly useful check: its official setup guide says an ANTHROPIC_API_KEY environment variable can select API billing instead of your subscription. If that was not intended, follow the official account-switching instructions before continuing.
Diagnose a rejected payment
| Check | Action |
|---|---|
| Service and billing eligibility | Claude’s payment help checks the card’s origin and billing address against supported locations. A foreign currency is not a foreign billing identity. |
| Address and authentication | Use the address registered with your issuer and complete any bank authentication. Ask the bank for the decline reason. |
| Duplicate billing | Look for an existing web or app-store subscription on the same or another login before purchasing again. |
| A charge but no access | Save the receipt, account email, time and amount; contact the merchant shown on the receipt. |
Compare the final amount and the exit
Read the final checkout currency, taxes and renewal interval. Compare that amount with your card’s conversion and cross-border fees. If you are only trying the service, one month gives you a clearer exit than prepaying a year. Record where to cancel and check whether cancellation ends renewal or access immediately.