Please log in with your admin account, and navigate to:
admin panel -> settings
scroll down to "Email Settings"
Make sure that they are set appropriately.
scroll down to "Alerts & Notices"
Make sure that alerts are enabled.
navigate to the "Emails" tab
click on the email that you are using for polling to create tickets.
Make sure that everything in there is configured correctly to reflect your email account and protocols being used, and that it is enabled.