Not receiving Email

I am currently not receiving all of the emails that are sent to me. Only very few are showing up in my inbox-whereas I usually get about 100 per day. They are not showing up in spam or any other folders, and this has continued for a week. I have tried test emails sent to me from other accounts and I have not received them.

I am seeing notifiations on my phone with the xfinity application for new emails, but when I go to open them, it does not show in my inbox.