I posted in this thread a while back about my ordeal with kLab as well. It was one of the most painful CS dealings i have ever had. it took like 20 emails over 2 months, and the whole thing was them asking for more info. I would give them 3-5 tidbits of info about my account, and it was never enough. they kept asking for more, for more, for more.
This was the most rage-inducing email (keep in mind this was about email #10 they sent me, after asking me for 4 or so bits of data each time, and me providing them as much as i could remember)
After a painful process of me giving them about 15 details about my account as i could remember them, they come back and say "thanks, but we really need a screenshot of a transaction you made". WHO THE HELL TAKES SCREENSHOTS OF IN GAME TRANSACTIONS.
My next email to them was very unfriendly. They caved and sent me a code to recover my account. Shitheads.