Why won't my Exchange Server emails open on my LG?

[AC Question]

I have several email accounts on my phone, using an app called CloudMagic. I have never had a problem with Exchange Server emails opening. Yesterday, all other emails are opening fine, but Exchange Emails from my office can be seen in the inbox list--but when I open them I get a message "The server has encountered a problem. Please try again later"

I've restarted device several times, deleted and reinstalled the account twice... still emails will not open. Help?!