Gmail desktop notifications on Safari not working (all settings checked)

So, my notifications are not working. I did the following:

1. In Safari on Gmail Settings checked "New mail notifications" and clicked on the link appeared above the radio button. Link disappeared and not showing again.
2. Allowed Gmail notifications in Safari settings Settings/Notifications/Websites/mail.google.com
3. Allowed Desktop notifications on Apple menu/System Settings/Notifications/mail.google.com

What else should I do?