Before you panic, mine looks dark most of the time because the screen sleeps after a few seconds of sitting idle. One press of any button wakes it. Caught me out on day one because my old device kept its screen lit.

Almost always a setting or a sleeping screen rather than a fault, and the fact it still fires normally is the clue - a device with a genuinely dead display usually has other problems too. Work through it in this order. First, the screen sleeps on idle, so press a button and see if it wakes. Second, check the device is not locked: five rapid presses of fire toggles the lock, and your wattage and airflow settings are preserved either way, so it is a safe thing to try. Third, remember three clicks of fire cycles the display modes - plenty of people land on the voltage screen, see a number they do not recognise, and assume the display is broken. Fourth, if the battery has dropped below about 20 percent the protection circuit starts trimming output and the device behaves oddly generally, so put it on USB-C for 45 to 60 minutes and retest from full. If the screen is still dark after a full charge, an unlock and a mode cycle, that is a hardware display fault rather than anything you have done, and it is a warranty conversation with your retailer. The reset guide has the button sequences written out if you want them to hand.

It was the lock for me. Pocket presses had locked mine and I spent an evening convinced the screen had died. Five clicks and it lit straight back up, felt a bit daft.

Charged it properly and pressed fire five times and the display is back to normal. Must have locked it in my coat. Good to know the settings survive that, I was worried about losing my wattage.