sleep prevented by sharingd

my computer isn't sleep well, because every time "sleep prevented by sharingd", could you help cover this problem!

localhost:SCT liyanbin$ pmset -g

System-wide power settings:

Currently in use:

standbydelay 10800

standby 1

womp 1

halfdim 1

hibernatefile /var/vm/sleepimage

powernap 0

gpuswitch 2

networkoversleep 0

disksleep 10

sleep 2 (sleep prevented by sharingd)

autopoweroffdelay 28800

hibernatemode 3

autopoweroff 1

ttyskeepawake 1

displaysleep 2

tcpkeepalive 1

acwake 0

lidwake 1