Let'sshow you how you can sync Gmail on all of your devices, including computers,
tablets, and smartphones, whether you're a home or business user. IMAP
(Internet Message Access Protocol) is an internet protocol that lets you
sync Gmail on alldevices. In most popular email apps, you can access your email on anydevice by using IMAP servers, including Gmail and Outlook. But you need to
check the sync settings in the Gmail app and ensure you've turned it on. This
feature should be enabled as a default, but anything can happen. You might
accidentally turn it off. You can check it under "Data usage."
See also -
my gmail not syncing,
Whyis Gmail not Opening