Smart meter installation - AIO problem

I've had a 3-phase smart meter installed by Octopus today. During the installation they turned off all the breakers on the Gateway (but not on the battery). I've tried turning the Gateway on again but its not functioning as it should. I've gone through the battery shutdown and restart procedure but this hasn't solved the problem. Both the battery and the Gateway just show a flashing green light. When I look at the app it shows the house consuming around 80w (when in fact its much higher then this as shown on the Octopus home unit) with the battery supplying this 80W (plus 2W being exported to the grid). Any ideas what's wrong and how to fix it? I think they've re-connected the Gateway output to the relevant consumer unit but I'm double-checking as the arrangement is quite complex.

when i had a smart meter fitted the engineer put the CT clamp back on the meter tail the wrong way round. First place to check and easy to swap round if the case. Also, with yours being three phase you will have three meter tails and i assume your inverter is single phase so you need to check if the CT is on the correct one.

The CT clamps are all in the Gateway unit so won't have been touched. Having examined the wiring I think the output leads from the Gateway that go to the main consumer unit have been routed via a Henley block that the input leads are also attached to so the input and output leads of the Gateway are connected together, hence nothing happening! I've emailed the installation electrician and are awaiting his comments. Battery shut down in the meanwhile as a precaution.

Turns out I was right, the smart meter engineer failed to copy the connections to/from the Gateway unit in the new set up (and didn't listen to me questioning it and pointing out it looked wrong). Eventually, I got the electrician who originally installed the Gateway to talk him through it on the phone. So beware when you have a meter change, those unfamiliar with the Gateway may think they know better and get it wrong.

When I get my AIO + Gateway installed, I also received an isolator box. So, the dumb meter was tied to the grid, and then to the isolator, and then isolator to the Gateway.
Sometime later, British Gas engineer swapped dumb meter to a smart meter. Replaced meter with two wires in, two wires out, grid, meter, isolator. He did not touch Gateway connections, so nothing could go wrong.