iPhone 6 Freezes When Responding to an Email

I recently update my iPhone 6 (AT&T) to iOS 10 and now every time I try to reply to an email using the stock email application or the Outlook app it will let me type one or two words and the phone will freeze. The account that I have setup is an Exchange account if it makes a difference. The phone does not freeze if I try to browse Safari or send a text message. How can I resolve this problem?