I used to receive an e-mail 8 hours before losing on time.Why don't I receive it anymore?

Check your settings in Online Chess -> Settings. Make sure that the option alert me when it is my move, I am running out of time, or I receive a challenge is checked under Game Alert Preferences.

It is checked,so what is the problem?

Not sure. E-mail filters maybe? I haven't let my games get that low on time so I don't know if it is working or not.

I received the warning today.It works again.

But today it didn't work again.Can the staff please take care of it,when you have the time?Thank you.