I have problems turning on my OnePlus 3

Connect the charger to the socket and to a wall socket.

When the battery charging icon is displayed, charging is in progress.

When the phone is turned on, you can always see the battery power level. The larger the coloured section of the battery icon, the more remaining battery power.

Press and hold On/Off until your phone is turned on.

Key in your SIM PIN and press the confirm icon. The default SIM PIN is 0000.

If an incorrect SIM PIN is entered three times in a row, your SIM will be blocked. To unblock your SIM, you'll need to key in your PUK. O2’s help guide will tell you how to get your PUK. Please note: If you key in the wrong PUK ten times in a row, your SIM will be blocked permanently. In this case, you need a new SIM from O2.

Press and hold On/Off.

Press Power off.