The title "Mortals" reflect the theme of the story because it manifests how everyone is concerned about the legacy they will leave behind.
We all die. However, we don't know the effect our lives have on others because these testimonies usually happen after our deaths. In the story, the man who was announced as dead was the one who gave the information about his death. He wanted to know how others perceived him when he was still alive. He wanted to know what legacy he has left behind. If it is a good legacy, that is very much appreciated but if it is a bad legacy, he will have the time to correct it and make said legacy a good one.