To enter a proper value in the IP address field, you must use a public address of your worker (RIG), not the local one. 


Windows: 

Open you browser and visit https://ezil.me/ip


Hive OS, RaveOS or any other Linux distro: 

Open command shell (Hive Shell, Rave OS Console, Terminal) and enter this command

curl eu.ezil.me/ip


If you are a new miner or have not been mining for more than 2 hours - to able to change payout settings, you have to mine on pool continuously with static public IP for 2 hours at least. After 2 hours, your IP address will become valid and you will be able to set your payout settings. This is security measure for all new miners.