Nov 2 2004
The boards which had 0 or less credit have now been reverted to the free plan. If your board suddenly has adverts, then this is most likely why, especially if you are on the azure server.
To verify this, and to fix it, look in your Admin Centre's "Credit" button - this will tell you how much credit you have. If you have 0 or less, you can then upgade your board by making a payment at your convenience.
Any questions, please feel free to ask.