Read!
I was about to give a one star review thinking mine were broken, but then just realized why maybe mine weren’t working. It seems one lantern was less sensitive, but the others constantly go off. Turns out, they go off when light hits them, that could actually be a bonus as you can leave them on, but be aware that means they can’t reliably be placed near fires and party lights outside unless you cover the sensor to make them think it’s dark. 
When they work, they look very cool!
Also note look best when sitting on something