There are 3 different LEDs on the front of your Atria Mesh 1200.
For each one, if the LED is green it means that it is working, if it is OFF or red it means that the corresponding function is OFF and if it is blinking in green or red it is doing a specific action, and you may need to wait for it to end or to restart the process.
Please report to the following detailed image for more information about each LED.