why does my script not run on wakeup

Question

I've followed istructions found on Run Script on Wakeup? to do the following: I have a ASUS Zenbook and since I upgraded to 16.04, the wifi stays disconnected on resume. I wrote a script that I can execute manually after wakeup (and entering the root pewd) and it properly hooks my wifi adapter up to my network. The script looks like:

$ cat wifi-resume.sh 
systemctl restart network-manager.service

so, following the instructions I created a script in /usr/lib/pm-utils/sleep.d/ called 96wifi-resume which looks like:

# cat 96wifi-resume 
#!/bin/sh
# On my ASUS Zenbook, this script is used to restart the wifi on resume.
# Date 11/04/2016 Ron Eggler

[ -f /bin/systemctl ] || exit $NA

case "$1" in
        hibernate|suspend)
                exit $NA
                ;;
        thaw|resume) 
                systemctl restart network-manager.service
                ;;
        *) exit $NA
                ;;
esac

permissions are set to -rwxr-xr-x 1 root root but it still does not seem to work, why not, what am I doing wrong here?

edit 1

However, I have replaced all the exit $NAs with exit 0 and it still doesn't seem to work correctly, however, when I call :/usr/lib/pm-utils/sleep.d# ./96wifi-resume resume from the shell, it seems to work as expected