Let's check if your device is just locked
Before we treat this as a defect, try the unlock sequence below — this resolves most "not turning on" reports.
How to unlock
1
Starting at the power button, press each of the 4 buttons briefly, one at a time, ending at the heat button.
2
Watch the light on the device as you go. If it turns red, the device just locked — repeat the same sequence again to unlock it.
3
A green light means it's unlocked. Try powering it on as normal.
Red = locked
Green = unlocked