lm1200 with mind of its own

Hi all, I am in the UK wit a giffgaff SIMS

I am trying to setup the modem as a failover 5G connection.

For the moment, i just want to try and get my laptop using it via the 5G.

Problems:

Can't change ip of device from 5.1 - just says error with a red bar.

Can't update firmware

When I put it into bridge, it does'nt seem to remember it

In fact the only change a can do is to select bridge, anything else gives me the error.

The 5G LED is Red, power is green.

Thanks!