L_TO_CONFIRM nista=0

I'm using L_TO_CONFIRM bapi to confirm pick + transfer TO. It's working OK in all cases, but It is giving error 7 when NISTA = 0 (confirmed quantity = 0).

Otherwhise, when I use LT12 in my system to confirm 0 quantiy in pick or transfer, SAP allow me to do it, so It isn´t a configuration issue.

Have you used L_TO_CONFIRM? How did you solve this case?

thanks in advance