For each payment, you can optionally enter a number up to 20 characters long, which can represent, for example, an order number, invoice number or any other payment identifier. All US ASCII characters can be entered (e.g. diacritics are not allowed). This can be done directly on the screen when creating the payment:
As a reminder
This number will be transferred to all systems and will also serve as a payment identifier in other reports and portals during transaction settlement. This makes it easier to match payments in your company's accounting system.