@open_book Very strange, it seems the module is trying to activate/deactive the monitor using the Relay, but you haven’t specified a relay to use.
I have noticed however, that
3 shouldn’t work. This variable is incorrectly named, it is not actually the pin number of the header, but the GPIO number instead. Refer to this Pi 3 image showing which “pins” correspond to “gpio” numbers. You should be using one of 4, 5, 6, 12, 13, 18, 22, 23, 24, 25, 26 or 27.
For example, a
4 would require the PIR io cable plugged in to pin header 7.