Why am I not getting notifications?

There are three places they can be switched off. Your phone can block them altogether — Settings → Notification settings says so when it does, with a button that opens your phone’s own settings. The type you are waiting for can be switched off on that same screen. And notifications follow the account signed in on that phone: sign out and they stop, sign in again and they come back. They are sent to the app rather than to the website.