> For the complete documentation index, see [llms.txt](https://doc.9http.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.9http.com/en/faq.md).

# FAQ

- [Product Problem](https://doc.9http.com/en/faq/product-problem.md)
- [How Do I Choose the Right Proxy Plan?](https://doc.9http.com/en/faq/product-problem/how-do-i-choose-the-right-proxy-plan.md)
- [Why does the proxy show as unable to connect in the fingerprint browser?](https://doc.9http.com/en/faq/product-problem/why-does-the-proxy-show-as-unable-to-connect-in-the-fingerprint-browser.md)
- [What is a CDK? Which plans support it?](https://doc.9http.com/en/faq/product-problem/what-is-a-cdk-which-plans-support-it.md)
- [Payment Problem](https://doc.9http.com/en/faq/payment-problem.md): Replace your auto-generated subdomain with your own domain, with automatic SSL.
- [What Payment Methods Are Supported?](https://doc.9http.com/en/faq/payment-problem/what-payment-methods-are-supported.md)
- [What If I Purchased the Wrong Plan?](https://doc.9http.com/en/faq/payment-problem/what-if-i-purchased-the-wrong-plan.md)
- [Do you offer a free trial?](https://doc.9http.com/en/faq/payment-problem/do-you-offer-a-free-trial.md)
- [How long does it take to receive the purchased proxy service or product balance after payment?](https://doc.9http.com/en/faq/payment-problem/how-long-does-it-take-to-receive-the-purchased-proxy-service-or-product-balance-after-payment.md)