I have configured two WAN interfaces on my router and aggregated them using mwan3. Among these interfaces, the one named WANcu possesses a public IP address, while the other interface named WANcm does not have a public IP. I have set up an OpenVPN server on this router. When the WANcm interface is disabled, the OpenVPN server remains accessible externally. However, when WANcm is enabled, OpenVPN connectivity fails. Could you please advise on how to resolve this issue?