Hi @FPOC 

please check Function Group for voucher type BA1. If Function Group = N, you have to cancel mixed payment or cancel matching for given transaction.

Best regards,

Adam

My target is to rollback partially the payment . If i cancel the mixed payment, the payment of all customer invoices will be cancelled. 

To rollback partially the payment you can cancel matching for the given transaction. 

Or you can try another solution:

1. You can cancel the whole mixed payment
2. Next you can use option Copy Cancelled Mixed Payment to register once again the same mixed payment
3. Next you can remove the invoice, which you want to cancel, from your new mixed payment
4. Finally you can approve the new mixed payment
5. In the result payment for only one invoice will be cancelled

The voucher type BA1 is linked with group function BGNU

The first payment was done with the transaction “customer payment” and the second is done with mixed payment. It’s possible to roll back complete or partial on the first payment but impossible to do the rollback on the second payment.

Do you know why?

Payments done with mixed payment can be rollback only with mixed payment.