> For the complete documentation index, see [llms.txt](https://docs.mailtrap.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.mailtrap.io/account-and-organization/billing/payment-issues.md). # Payment Issues Troubleshoot common payment issues with Mailtrap billing. Learn how to fix zip/postal code errors and CAPTCHA token problems when adding payment methods. If your payment fails, please first check the validity of your credit card details and available funds. If everything is correct but the issue persists, please contact your bank. ### Zip/postal code error While you add a payment method, our billing system sends the payment request to your bank where the card was issued. The zip/postal code error occurs when your bank sends data back to our billing processor. In most cases, customers try to use their home or office postal code. This error can occur when the credit card is registered to a different postal code. In other cases, a customer has moved to another place and enters the new postal code, but the bank still links the old code to the credit card. ### No valid CAPTCHA token This is a rare error that may be caused by JavaScript blocked by a browser extension. Please try using a different browser or using incognito mode. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation by asking a question. Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters: ``` GET https://docs.mailtrap.io/account-and-organization/billing/payment-issues.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.