When it comes to customer support, Nexon is one of the worst. I remember the big "hacking session" that occurred on Dungeon Fighter Online (DFO) back in Fall 2011. Almost 40% of players had their accounts hacked, myself included. It would take months to over a year for Nexon to give a response to a ticket, that is IF the person ever received a response. Most of the time they claimed that they couldn't give back the avatars or gold that the player lost, so they would just hand out a handful of NX credit (which is used to buy items on the game) to the player. I've known a few people who spent over $100 dollars on NX credit on DFO. One of them never got a response from Nexon after he got hacked.
Eventually, a lot of people stopped playing DFO. The player population became so low that Nexon shut down all American servers for DFO. If Nexon had built better security in their game and actually helped players resolve their hacked accounts, they would never have to shut the game down in America.