I asked above about the PIN as that is often the reason ad serving has been stopped and the second stage was to suggest you send in the form referenced by gddsmith which you have also done. It appears that they have disabled ad serving to your url whilst your account remains active. I say 'appears' because that seems to be the case based on the info available. As such I've asked the Adsense staff to resend the email with the issue ID.

If you get that email (and it won't be sent immediately not least because, as I write this, its 1:46 am Adsense time Sunday morning and they don't work weekends) be aware that if you make an appeal its a one off opportunity so ensure you make a strong case.