Cannot Access My Mikrotik OPENVPN server through pppoe-out1 IP

Hi, I have successfully set up OPENVPN server on Mikrotik, i can access my OPENVPN through WAN1(dhcp client) IP successfully, but I have problem accessing my OPENVPN through WAN2(pppoe-out1) IP, altough it’s dynamic IP but I have configured ddns for the dynamic IP and ddns can be resolved with correct IP address. I have other port forward on WAN2 interface and I have no problem accessing it. That means the problem is not dynamic IP and my provider didn’t block my connection port. I have already open firewall with command /ip firewall filter
add action=accept chain=input comment=“OpenVPN” disabled=no dst-port=xxxx protocol=tcp. Are there anyway to make mikrotik’s OPENVPN server accepting connection from all WAN port, thanks.

Have you setup any type of connection tracking, so that traffic that came in on the PPPoE-Out1 conneciton, also leaves through it, and the responce traffic isn’t trying to go out your WAN1 conneciton?

I tried making a connection monitoring on pppoe-out1 chain input, openvpn port, it does recieve TCP(SYN) when openvpn connection request was made, but the mikrotik openvpn server does not responded. How to make the OPENVPN server accept the connection request?