Running script on Tun0 up

Hello,

I am trying to run a small script after i connect to a vpn server.

My understanding was that putting a executable script in
/etc/network/if-up.d would run the script after a network interface is created.

reference the hook script parts:
https://manpages.debian.org/buster/ifupdown/interfaces.5.en.html

just for test purpose i put the scrip in /etc/network/if-ip.d

upvpn

#!/bin/bash
echo “tun0 up” >> /var/log/tun-up.log

when i connect the vpn nothing get written in the log.
I am on the right track? or all of this is wrong.

For info this is on Debian 10
im calling the vpn using the command
systemctl start [email protected]
the vpn work just fine

Any help would be greatly appreciated!