Integrate LinkPay callbacks

To receive a callback after successful or failed payment, you have to specify to which URL it will be sent:

1. You have to specify the URL under your E-shop settings by clicking on the e-shop
2. In the “Payments” section, you have to fill the “Callback Notification URL”
3. After each payment you will receive a callback with payment_reference and order_reference
   
4. When you receive a callback you can request payment status using payment_reference, by using GET /payments/:payment_reference endpoint (more detailed information can be found in the API documentation, section Callback Notification)