Problem with sleep mode.

Hello,
I cant put my htpc ( j3060, 4gb ddr3, chieftec bravo cs-03b-b(psu 300w), 120gb ssd, 4tb hdd, kodi 17.1 ( last libreelec)) into sleep mode. When i choose ‘Sleep’, pc act like its going to shut down, screen goes black, fans stops but after few seconds (1-3s) it back to the state before i clicked ‘sleep’.
Are there any options in kodi preventing sleep mode?.
After my last try when i changed some options in bios and kodi, pc couldnt be closed. All the time when i choose power off or close after x time, pc went on sleep mode. I reseted bios settings to default but it didnt fix it. I had to reinstall libreelec… So at this time i am going to ask first