HI and Welcome to Auctiva HBK7676. Not sure if I can be of much help, but I'll try. First of all what browser are you using? And most importantly are you SURE your item didn't post to ebay? Have you gone to ebay to make sure?
Other questions I have are can you save the ad? if your sure it didn't post, then save it. Select the box next to the listing you want posted then hit post up top, does that work?