Manga Return Survival

Is it evil fate or a blessing? Suddenly I realized that I was once again awake in a world free of zombies. For three years I was in painful wanderings, hiding from these flesh eaters, until I finally gave up and voluntarily went out to meet the horde of zombies. However, opening my eyes, I realized that I was in the past, exactly six months before the spread of the ill-fated virus. Will I be able to save this world, or is this another punishment for me?