Please make sure that all your units are plugged in during the reset procedure.

To reset your parent unit:

•  On the left side of the base of the monitor (parent unit), you should see a small reset pinhole. 
•  Using a pin, or something small enough to fit inside, press and hold the reset button until your monitor (parent unit) powers itself off. 
•  After what can take up to a minute, your monitor (parent unit) should then power itself back on. This will indicate that the reset has been completed successfully.