I appreciate the info, I'll definitely try it. Thank youI just researched other forums for you. There are many people having the same issue. The fix is to delete your yahoo account off your phone and than put it back in again.
http://www.ipadforums.net/ipad-general-discussions/90217-yahoo-mail.html
http://forums.macrumors.com/showthread.php?t=1449174