I have noticed that if I am on the calendar (this year) for my property, at the top left as an option to click, "Reservations." Next, under the bolded word, Reservations, I click, "All" and this allows me to access past reservations from other years. Beside the word, All, is "filter." Click this and you can choose what dates you want to access. Next, click the green box, "Details," to the right of an individual reservation and you can see more information, and from there click, "Messages," and you can see the written message conversations you had with past guests.