Emerging scholars add a new reference?

My reference never sent in their evaluation and I have been unable to contact him. I know he doesn’t check his email that often, and it’s possible my high school’s email stuff is down during the Summer since I can’t get into my email. Is it possible to add a reference at this point?

How do you know your reference did not send in his eval since you have been unable to contact him? Did UA let you know they had not received? I would call and explain the situation and ask UA what to do with your application.