iphone mail app not receiving e-mail from 1 sender

The Mail app on my iPhone 6/iOS 8.3 is not receiving e-mail from one sender sent to my Outlook e-mail account. This sender's e-mail address is "...@rbdigital.onmicrosoft.com". It is a notification of digital magazines available from Zinio. I know the mail app is not receiving the e-mail because Outlook 2013 on my desktop and Outlook.com do receive these e-mails. How can I get the mail app on my iPhone to receive these e-mails from this address?