Comcast Business Modem, Static IP and Unifi VPN
I'll start by saying I know enough to be dangerous, but I'm definitely not a pro at this stuff.
I run a small business, which means I'm also my own IT guy. I use Unifi networking gear downstream of the modem and at one of my sites I recently had to reset a modem that hasn't been touched in 18 months. Previously, I was able to use my Unifi remote VPN to access this site, but it is now blocked.
Nothing has changed on the Unifi end. On the modem I have set it for pass-through mode (I think) - I have been told Bridge Mode won't work, and that to place it into pass-through mode I simply needed to turn off the Firewall altogether, "Disable Firewall for True Static IP" is checked, and disable DHCP (which was because of the static IP).
What am I missing?