Hi
Antoni,
As per documentation:
"For Datagramm and Transactional modes, the SMSC will try to immediately deliver the
message to a destination. If it is in Transactional mode, the SMSC will also return a delivery
result (success/failure) to the ESME. Such messages are not stored in the Cassandra database.
In case of delivery failure the message will be dropped and no more delivery attempts will
be made.
"
So all you have to do, is to set your SMSC in Transactional mode
Best regards,
Sergey Yashchenkov