LHGG LTE Kit no signal

I've got 2 LHGG LTE Kit devices that have worked fine for 1 year until they were removed from service 6 months ago.

I'm now trying to get one back up and running but having issues. Neither of the devices seem to get any signal.

I've put 2 different fresh SIM cards in both devices plus my own known working SIM from my personal mobile. I've also checked the other sims in a phone, they work fine and get a decent 4G signal. I can browse the web with all SIM cards when used in a phone.

One SIM is on the EE network and the other is on the 3 network. I have the dish pointed at my nearest tower which is direct LOS and just under 1kM away.

I have the APN set up correctly for each network.

What am I missing here? I find it hard to believe that both devices have died whilst in storage.