A Default Address is a catch-all email address which collects from senders that may have misspelled or may have entered an invalid email account associated with your domain name.
Here are the steps on how to create a default address:
Step 1. Log in to the cPanel using this link format: http://yourdomain.com/cpanel/
Replace yourdomain.com with the Main Domain Name connected to your hosting.
Step 2. Click Default Address under Email panel.
Step 3. You can delete the message by choosing Discard option:
Or, you can choose Forward to Email Address, and type in the correct email account.
Step 4. Click Change to save.
Once this is done, either your email messages will be deleted or forwarded to the correct email account.