Alzhao, thank you for getting back to me so quickly.
I’m pretty sure that the firmware is not up to date on the sub node (it is on the main node), but I don’t know how to update it if it isn’t connected to the internet.
I can try again to reset the sub node (pin in hole for 10 seconds) while power is on and see if it works this time (it didn’t before). Do I need to turn off the power on the main node while I do this?
Thank you.