Can anyone help?

Trying to use a remote 350 phone directly via Pub IP to Draytek IPPBX.

The phone registers OK but when I make a call no joy and says disconnected on screen.

I could setup a VPN between the two routers, but would prefer over Pub so i can move the phone between locations easliy.

As usual lots of references to the ability to do this but no instruction on how to do it (page 32 of manual)!

Any help is appreciated.