How to fix windows 10 maill app which won't auto sync?

[Windows Central Question]

First time I install windows 10 in my pc, mail app works normally. New mail come, and I got the information from the live tile.
But somehow that doesn't work anymore. I only got mail if I manually sync in my mail app and it bothers me a lot.
Now I have version 1511 of windows 10. Do you have any suggestion to fix this problem?

Thanks for your help.