pt-table-sync error "The server specified as a master has no connected slaves"

pt-table-sync error: “The server specified as a master has no connected slaves at /usr/local/bin/pt-table-sync line 6835.”

A command I used just to see sycn statements:

$ /usr/local/bin/pt-table-sync --print --verbose --sync-to-master h=localhost,u=myuser,p=mypassword
The server specified as a master has no connected slaves at /usr/local/bin/pt-table-sync line 6835.

Master host ans Slave host are connected through ssh tunnel to each other.

Master and Slave locally work on port 3306, socket /var/run/mysqld/mysqld.sock
Master connects to Slave on port 3317.
Slave connects to Master on port 3307.

MySQL 5.6.15
pt-table-sync version 2.2.10

Please, help.

Thank you.