I got my Macbook as a Christmas present this year, used. I noticed that when I close it, it takes about a minute for it to sleep (only because I set it to sleep after a minute of inactivity). Then, when I open it, it doesn't wake until I press something. I've tried doing many things, including "pmset -g assertions" and the only thing preventing it is "com.apple.iohideventsystem.queue.tickle" but it doesn't say anything like "preventsystemsleep". Is the sensor broken? How would I fix that?