If you are not able to find messages in your Inbox, Favorites, or Archived folders that were previously there, it means that the person connected to that message is no longer advertised on site. When someone chooses to deactivate their account or the support team removes them from site, any messages they have sent will be automatically removed from the Inboxes of those they have contacted. This is done to ensure no one is replying to people who are no longer looking for a match or who are not valid users.