Enewsletter is not sending test emails


Can you look at this please (something is wrong with E-Newsletter and Protected Content email sending to users and with admin notices). I think both of these use similar code or methods. I have been up and down with the hosting provider and wpmudev on this.

See here for more info: https://premium.wpmudev.org/forums/topic/emails-to-users-and-notices-to-me-have-stopped-for-pc-and-other-wpmudev-plugins?replies=5#post-844416

Also, Subscribe By Email is working perfectly as is regular notices from the website from other plugins too (and WP core email).