Config nmcli auto wifi connect

I tried to conifg a systemd service that use nmcli connect wifi at system startup, so I can debug board with ssh directly and save cable connection.I am not familiar with systemd and add service reference to netcfg and v2ray. such as
rock@rockpie:/etc/systemd$ cat system/wificon.service
Description=Auto WIFI connect at startup

ExecStart=/usr/bin/nmcli con up home


it not work. and journalctl -b -1 seems have not any relative info

ok, I take a roundabout to auto startip wifi connect.just add command to /etc/rc.local

rock@rockpie:~$ cat /etc/rc.local
#!/bin/sh -e
# rc.local
# This script is executed at the end of each multiuser runlevel.
# Make sure that the script will "exit 0" on success or any other
# value on error.
# In order to enable or disable this script just change the execution
# bits.
# By default this script does nothing.
/usr/bin/nmcli con up home

if [ -e /etc/first_boot ]; then
    /bin/sh /etc/first_boot
    rm /etc/first_boot

exit 0

maybe crontab or add to /etc/init.d also feasible.but there remain a flaw is every time connect to wifi will lead to kernel oops.I encounter such situation in company’s product haven’t write keymap, which use 8821cs while it is 8821cu in rockpi E.I thinks it is a common confusion.Any one have a good solution?