The first step is to contact SimplePay to indicate your intention to join. You can do this on their contact page.
After your message, an OTP representative will contact you, and the contracting process will start. There is an OTP set-off fee for joining, which has been around HUF 50,000 in recent years.
If everything goes well, you will be given access to the Sandbox account, which will start the test integration. An earlier post explains using test account.
After the integration and setup, OTP will test the connection. If they find a bug, they will report it, and you will have the opportunity to fix it before they view the interface again. If everything is OK, you will be given access to the live account, which now handles actual transactions. All we have to do is set up the appropriate IDs (which we get at this point) - as we did for Sandbox - and you have a live extension on the WooCommerce side.
After that, you have the credit card payment gateway available in our store.
For more information, visit SimplePay FAQ!