Emails aren’t being sent out

I am having an issue with any emails of all kinds being sent out via Mailpoet plugin. If I send a sample of the email wanting to be sent out, or the blog post being sent out via newsletter, I have one email address out of eight or so that it actually is received by. But even that email address doesn’t receive the automatic newsletters (the one where I say that I want the newsletter to go out every morning at 9:00 am). It says that it was sent to 5 out of 5 but none of the email addresses receive it. I have contacted my host (GoDaddy) about the issue. And they can’t for the life of them figure out why it’s not working. They said that it almost has to be the plugin. I have searched the posts but don’t see any real solution to the issue. Can someone please help me?