Why is my yahoo Inbox mail going to trash after a few hours?

Mail that arrives in my Inbox is now going into Trash automatically after a short period of time. Also, the email that I put in Drafts also disappearing. I proved this to myself by taking a screen of mail in my Inbox one evening. The next morning that mail was in my Trash. That included both read and unread mail.|||Make sure there isn't a filter that does that. Chech your filters.