iPhone email notifications not working can be a pretty troublesome issue. It is so, especially for those users who don know how to fix it. An effective way to fix it is to change the new email push and fetch from the mail app's settings. You can do it by going through these steps.
Launch 'Settings' on your device.
Scroll down to 'Mail.'
Those who are using iOS 13 and earlier versions can go to the 'Accounts & Password' option.
Navigate to 'Accounts' and choose 'Fetch New Data.'
Now, find all email accounts added on your phone and manage the notification individual account.