UPDATE: We’ve finally heard back from Yahoo. They’re claiming Florian’s account was not “lost” but taken offline for spamming.
According to Yahoo’s Kristen Wareham, “In researching his specific situation, we have come to find that his account was taken offline for quality control reasons. Our customer team reached out to Florian to explain that it had nothing to do with our new advertiser system or import tool but rather due to the lack of quality with his keywords which were not tied to any content. This is standard procedure for handling advertisers who spam our system.”