My screen goes black and won't come back on in sleep mode

My note is only a year old and still like new, but when I press the power button to put it into sleep it doesn't come back on. The buttons light up at the button but the scree stays dark through the lock screen. After a while it shuts of if I hold the power and home button but when it reboots it does it again every time. The screen lights up until I put it in sleep. Any suggestions?