registering service name with 2nd listener

Hello all,

Question. I have 2 static listeners on 2 different ports and the service name is only registering with LISTENER. How do i get it to register with the second listener.

Linux redhat-7

Oracle 12.2 non pdb

LISTENER port 1521

LISTENER_2 port 1555

show parameter service_name

service_names            ora_1.skynet

Thanks

Dave