problem with emailing

[lilivo]

i'm using the regular emailing functions for the diamond. just created a new account using my yahoo mail. for some reason it works for about a day and then it starts saying for me to login, and i know my pass is correct but it will never go past that screen. what email apps are u guys using? i tried seven but my battery drain is terrible already without using an app that uses that much battery. so does anyone have another idea? or maybe a suggestion on how to make it work properly. any help is appreciated