Sending packets via UDP in erlang

Question

so i'm trying to send udp packet to a listening port on a computer which is not connected to the same LAN but has internet access via gen_udp in erlang.

I start my first node by opening the port ({ok, Socket} = gen_udp:open(8887).) and the open the port on the other node the same way, When i send a packet from one node to the other via gen_udp:send i don't receive anything (trying flush() on the receiving node), So i'm wondering if there is something i'm doing wrong ? , i checked the firewalls and erlang and epmd is permitted.