Mask Won't Turn On Or Only Turns On When Plugged In
To turn on the mask you need to PRESS and HOLD the button on the mask for a solid second. It will then power on.
Notably, you can gently tap on the power button when it's plugged in to power it on which leads to some confusion. But as long as you press and hold when it's not plugged in you should be good to go.
Same goes for turning the mask and neck plate off. Press and hold for a solid second.