Earlier today Daum posted an announcement that they had created a new member database for the game. Due to this change some accounts will need to be re-verified before you can play again. If you are re-directed to the page shown in the image below, you will need to confirm your I-Pin or Phone number for the account. 
Newgameway offers re-verification for $3 if you bought an account from them. Any accounts bought after 24th of July will have a free re-verification. You can use this link and enter your User ID and Password to buy a re-verification: http://www.newgameway.com/product.php?a=timecard&gid=90
Due to the amount of people who will be buying a re-verification, please consider that it may take a while for you to hear back from them.
Sources: http://bbs.black.game.daum.net/gaia/do/black/notice/read?bbsId=BN001&articleId=482
https://www.reddit.com/r/blackdesertonline/comments/3eve6m/people_getting_banned/
