Laptop will not suspend on lid close

Question

I am having an issue where closing the lid on my laptop will not suspend.

System

Dell XPS 15 7590
Ubuntu 20.04.1 LTS
i3 version 4.17.1 (2019-08-30)

Steps taken to fix

Check suspending manually work

Both sudo pm-suspend and sudo systemctl suspend work just fine. I can suspend and resume by running them directly.

Ensure logind config is correct

~ cat /etc/systemd/logind.conf

HandleLidSwitch=suspend
HandleLidSwitchExternalPower=suspend
HandleLidSwitchDocked=suspend
#LidSwitchIgnoreInhibited=yes

Check lid switch is not disabled

~ grep -i lid /etc/UPower/UPower.conf

# Do we ignore the lid state
# Some laptops are broken. The lid state is either inverted, or stuck
IgnoreLid=false

Check lid closing is detected

~ journalctl | grep -i " lid "

Aug 20 09:27:54 nuitari kernel: input: Lid Switch as /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0C0D:00/input/input0
Aug 20 09:27:54 nuitari kernel: ACPI: Lid Switch [LID0]
Aug 20 09:27:57 nuitari /usr/lib/gdm3/gdm-x-session[1216]: (II) config/udev: Adding input device Lid Switch (/dev/input/event0)
Aug 20 09:28:07 nuitari /usr/lib/gdm3/gdm-x-session[2212]: (II) config/udev: Adding input device Lid Switch (/dev/input/event0)
Aug 20 09:28:19 nuitari systemd-logind[1004]: Lid closed.
Aug 20 09:28:19 nuitari kernel: ACPI: button: The lid device is not compliant to SW_LID.
Aug 20 09:28:37 nuitari systemd-logind[1004]: Lid opened.
Aug 20 09:41:14 nuitari systemd-logind[1004]: Lid closed.
Aug 20 09:41:27 nuitari systemd-logind[1004]: Lid opened.
Aug 20 09:41:36 nuitari systemd-logind[1004]: Lid closed.
Aug 20 09:41:42 nuitari systemd-logind[1004]: Lid opened.