The conditions for loading a document into a payment order are as follows:
"Payment prohibition" is not checked (visible only on FAP, ZAV)
The bank account on the invoice matches the bank account on the payment order
The recipient's bank account is specified on the document
Total amount > 0 and the module is FAP or ZAV, or total amount < 0 and the module is FAV or PHL
The payment status is blank or is other than "Paid" or "Paid manually"
The invoice has not been cancelled
The "In payment order?" column on the invoice is blank or is other than "Payment order sent" (this column is set automatically)
The currency of the invoice matches the currency of the payment order
The payment method on the invoice is blank or is set to "Bank transfer"
Additionally, the invoices must not have been previously loaded into the same payment order.
If none of these conditions resolve the issue, check the format settings for payment orders on the bank account. For example, the SEPA XML format cannot be used for a CZK account (it is available only for EUR transactions and domestic payments in CITIBANK).