Help Exchange Email Not Syncing

[millcroft]

My Microsoft Exchange Outlook email was syncing properly on my Galaxy S4 up until yesterday afternoon but now won't show up at all. All of the ActiveSync boxes are checked and it's set to sync automatically but when I check it it says it's syncing as of the current time/date but when I look at the settings it shows the last sync as yesterday afternoon. Any ideas on how to get it to start actively syncing email again? Thanks so much!