It is pretty simple. We cannot get any mobile connection using a VF sim. We have tried 3 different VF sims 2 x Unlimited Max sims and 1 that had a data cap, but had plenty of data left. We have tried with Auto and Manual APN settings Auto and manual DNS settings.
Putting a sim from another provider works within a minute or so. We have tried Three, O2 and Asda sims all work as expected. VF sims just do not seem to work. As you can see from the pictures in my other post https://community.teltonika-networks.com/35141/rut-x11-mobile-internet-not-working-from-any-lan-wifi-clients
the VF sim connects correctly shows connected and registered get an IP from the VF network. We spent a lot of time with VF 3rd Line Technical support who also confirmed they could see the device was connected. But alas no service. They concluded that it was a Sim Version incompatibility, whatever that means.
The product code? This is a RUTX11
The device is approx 30 miles away installed on a yacht.
I did send you a PM last week.