Can't connect to FreePBX over VPN

Hi, I am new to FreePBX and I am having an issue. I have a remote office with a VPN using OpenVPN. I can ping and connect to workstations and other devices across the VPN just fine. However, I cannot ping or connect to the local PBX from the remote site. I have added rules using the command iptables -A INPUT -s -j ACCEPT but still nothing. I’m sure I am missing something but I have no idea what it could be. Any help would be greatly appreciated. Thanks in advance.

I have a working config with OpenVPN on freepbx server connecting a remote office. Were you able to solve your problem? If not, I should be able to help by comparing our configs