Hello Thiago.

Thank you for your purchase.

Issues like this usually happen when you leave the "Test" or "Sandbox" mode on, and you're trying to pay with live credentials or a real credit card. Also, you're not able to process test credentials for Live payments

Please open Amelia Payment settings, and check if you've enabled test or sandbox for PayPal and Stripe, and if you have switch to Live. After that you should be able to take real transactions.

Please note that PayPal and Stripe have the minimum amount set to (I believe) $0.5. If you set the price to be lower than that, it could also cause issues.

If you still cannot get it to work, please provide me a temporary WP-admin login for your site where this happens, so we could log in and take a look ‘from the inside’ as that’s the most efficient way to see and resolve the issue. We do not interfere with any data or anything else except for the plugin (in case that’s a production version of the site), and of course we do not provide login data to third party. You can write credentials here just check Private Reply so nobody can see them except us.