Payment error in Free Fire when purchasing diamonds

I am not seeing anything about a payment error. If there is one then please include the message.

For your network error here are things to try:

If you are using a VPN try removing it completely (don't just turn it off) and see if you can then use the service. E.g., AppStore - Apple Community

Restart your equipment and/or sign in out and back in again, and try again.

If using cellular data (even if it is seemingly good), try using WiFi instead. —> Connect to Wi-Fi on your iPhone or iPad - Apple Support

If you are trying to use a service from outside your Home Country it may not be available. From: Apple Media Services Terms and Conditions - Legal - Apple Media Services - Apple

- A. ”Our Services are available for your use in your country of residence (“Home Country”).

And: "Certain Services and Content available to you in your Home Country may not be available to you when traveling outside of your Home Country."