Improving email deliverability
If you're having trouble sending out emails, there are tools in your cPaenl that can assist you with this.
On this page, you should click the "Show All" button.
After that, it will list all of your emails and the associated status message.
The next tool is the Email Deliverability page in your cPanel.
On this page, click "Manage" next to the domain encountering issues and you will be able to see a list of errors and suggested fixes.