Navicom RT-850 VHF GPS Problem

[stevenit]

Hi Sailors,
A brand new Navicom rt-850 installed.
His own gps worked until I inserted MMSI number, after that, no more gps signal.
I connected with gps caming from my old FURUNO NAVnet and it works.
What do you think?

Original gps problem/version?
VHF software version? (is it possible to update it?)

Thanks and fairy wind.
Steve.