So we had a smart meter fitted and then received an email to say that it can’t talk to Bulb to send readings. I read that is uses the mobile phone network. What I don’t understand is that the display unit inside is connected to my wifi so why can’t it fall back to that to send the readings?
Because that’s just not how it’s designed to work. Smart meters do not use customer-provided data connections. You’ll find that the “smartthings” integration will still work, since that does send data via your WiFi. Just not the actual readings used for billing purposes.