Hi @Gareth68
Welcome to the Sonos Community!
Looking at your diagnostic, and given what you’ve already tried, I recommend rebooting your router as @GuitarSuperstar suggests. I’d add that you should also reboot your BT WholeHome extenders too. Keep the Move closer to the main router than it is to any of the extenders while doing this to maximise the probability that the Move is connecting to the main router. When the system is online again, please test without moving the Move.
If the Move works more reliably while connected to your main router, you may want to move your WholeHome extenders closer to the main router.
It’s also probably worth checking your command history in the Alexa app when things don’t go well, to make sure Alexa understood you properly. Alexa > More > Activity > Voice History.
I hope this helps.