The notice from eBay would have explained there was probably a violation. eBay will not say more than that.
The email tells you how to proceed from here:
We're writing to let you know that this listing for an item you won or bid on is no longer available:
We understand this may be disappointing, but occasionally we need to remove listings. In some cases, the item itself is fine, but was listed in a way that didn't follow eBay's guidelines.
Here's what you can do next:
-- If you already paid, received your item, and you're satisfied, please disregard this notice.
-- If you won the item but haven't paid, don't pay. Since eBay removed the listing, you're no longer obligated to go through with the transaction.
-- If you already paid for this item through eBay, and it's past the estimated delivery time, you can open a case in our Resolution Center. Click the link below, and select the "I haven't received it yet" option. This will guide you through the process of opening a case. http://resolutioncenter.ebay.com