To register the email in cpanel please follow the below steps:
1: Open the Cpanel with the login details you have received on your registered mail.
2: Under the EMAIL section click on the option "REGISTERED MAIL IDs".
3: When you click on it you will get the option to fill the email name under email_id option once you done click on SUBMIT.
4: Once you click on submit it will take maximum 3-4 hours for your email to get registered.
NOTE: **You always need to register the email id when ever you run the php script or using any plugin to send emails**
