I have had this problem in the past and it reemerged on an upgrade from 16.04 to 18.04 and have resolved it. For me (Lenovo Yoga) the issue is with USB rewaking the machine.
The following fix worked for me. 1) Created file: /etc/systemd/system/toggle.XHC.to.fix.suspend.issue.service with following informaiton [Unit] Description="Make suspend ignore USB wake up." [Service] ExecStart=/bin/bash -c "echo XHC >> /proc/acpi/wakeup" [Install] WantedBy=multi-user.target 2) Created a symbolic link to above script in /etc/systemd/system/multi- user.target.wants 3) Executed following commands sudo systemctl daemon-reload sudo systemctl start toggle.XHC.to.fix.suspend.issue.service 4) checked service was started with sudo systemctl status toggle.XHC.to.fix.suspend.issue.service 5) Enable it on boot with sudo systemctl enable toggle.XHC.to.fix.suspend.issue.service Last steps are based on https://www.reddit.com/r/archlinux/comments/3zxg65/how_to_permanently_change_procacpiwakeup_or/ -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to systemd in Ubuntu. https://bugs.launchpad.net/bugs/1574120 Title: Notebook doesn't suspend when lid is closed after update to 16.04 Status in systemd package in Ubuntu: Confirmed Bug description: My notebook does not suspend after upgrading from 15.10 to 16.04. According to system settings the notebook should suspend when lid is closed but actually this does not happen. Instead it continues to run as if nothing had happened. With the previous versions of ubuntu (14.04-15.10) everything worked fine. My System: HP Pavilion dv7. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: acpi (not installed) ProcVersionSignature: Ubuntu 4.4.0-21.37-generic 4.4.6 Uname: Linux 4.4.0-21-generic x86_64 ApportVersion: 2.20.1-0ubuntu2 Architecture: amd64 CurrentDesktop: Unity Date: Sat Apr 23 23:11:15 2016 InstallationDate: Installed on 2015-10-29 (176 days ago) InstallationMedia: Ubuntu 15.10 "Wily Werewolf" - Release amd64 (20151021) SourcePackage: acpi UpgradeStatus: Upgraded to xenial on 2016-04-22 (1 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1574120/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp