Please check the LEDs. If all the LEDs are off:
• Ensure that power is restored to the wall switch at the circuit breaker.
• Verify that the wall switch is wired correctly.
• Confirm that your primary switch has been installed in an electrical box with both live and neutral wires. If you are unsure, switch the installation positions of your primary and add-on switches and try again.
You may have wired the other switch incorrectly. Please turn off the power at the circuit and check your wiring as illustrated in the user guide.