OIT is making some changes to increase Gmail security, which could result in more emails landing in your spam folder. We strongly recommend you check your spam folder regularly in the event that a legit email gets identified as spam.
Gmail uses machine learning to understand your preferences better and to recognize spam. When you manually mark a message as “Not Spam,” Gmail learns how to manage messages addressed to you.
You can manage their personal contacts list in Gmail. By adding an external address to your contacts list, Gmail knows not to mark messages from those senders as spam.