On my answering machine, I got a message from Koichi saying he's flying to Hawaii tomorrow.
He challenged me to a debate on my answering machine.
I've been calling the Tofugu office over and over again, but I always get the answering machine.
You hopefully know that this has something to do with housesitting (留守番). So, a telephone (電話) that does housesitting for you is what? It's your answering machine.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.