if I remember rightly it's something to do with your actual network settings. it's how many times by default your phone actually rings before it goes onto the networks answer machine. can't quite remember how I did it as it was many moons ago but I'm pretty sure it's not possible on your phones settings but if you query it on Google with the specific name of your network the answer will make itself known. hope that helps and good luck sorting it out 👍👍👍
