You do need to synchronize your mail in order to receive the emails. Sometimes there’s an error in Gmail syncing mail. Usually, it is because of the settings change that you might have forgot to enable. Let’s take a look at the steps on enabling Google mail sync.
How to sync Gmail?
· Open your Gmail application.
· Now, click on settings.
· There is a menu on the left side of the screen.
· Then, click on your account.
· You will see an option on sync Gmail with a box beside that.
· Click on the box to enable it.
Read more: gmail sync settings