Posting here in case someone at Blizzard can help us. There is a massive issue right now that is affecting more and more players which does not allow them to log into their account. This is account specific as they can log into an alt account but their main account does not get into the game despite doing all the troubleshooting steps provided by Blizzard CS.
Link to my forum post for more info: LC-208.001 / Server Error- Account-Specific, Not Network-Related