Update!
With the Chat option i could find a great person at Nakivo and i succeeded in setting everything up.
The Qnap Nakivo Transporter version that my NAS was offering to update (v9.4.0 July 2020) turned out it was OUT OF DATE !!!
So i updated the Linux VM of Nakivo Backup & Replication to the latest version 10.
Careful that Nakivo Transporter V9.x can't work with Nakivo Backup & Replication version 10.
Then with the great help of the chat guy at Nakivo i could find at Nakivo website ( https://www.nakivo.com/resources/download/update/ ) the right QNAP Transpo