Always ON - Multi-Site Failover scenario: Listener name should be one or two?

I am configuring ALways ON on Multi-subnetFailover scenario.

Listener names: Listener1: 172.20.12.1 Listener2: 172.20.15.2

While creating Always ON Availability Group(AAG), in Availability Listerner tab,...

It asking below details

1. First listerner adding Listener DNS name: Listener1 Port#: 1433 Network mode: static

2.While 2nd listener adding , there is no option to give "Listener DNS name" for 2nd listerner.

Listener DNS name: Listener2 ? Port#: 1433 ? Network mode: static?

Question : is the Listener name should be same name for both listerner IP's for multi-subnet scenario? Is something like this... Example: ? ListenerName: 172.20.12.1 ListenerName: 172.20.15.2

So that client can use listerner as "ListenerName" to connect to primary server whihc over is up?

Thanks