Currently going round on circles with 'Peter' on the web chat.
He's currently going through his list of prompts to diagnose the issue from his end. He's just told me to turn off my router by pushing the button on the side. I have an Eero. He then asked me to confirm that the red light is not in fact the power light.
I'll try powering off the ONT again when he's gone through his list, but I suspect that the lack of Service light means that there's an issue with the network.
I can't see an outage reported, but these things can of course happen locally. Try switching the ONT off for a full 30 minutes at the mains before turning it back on again. Let us know if that helps, or not.
