It was never your gold - it belongs to k2.
Just like your raptor+9, your level 83 character, your IN+2, your everything.
Nothing belongs to you, you just pay k2 to use it.
It doesn't mean that I agree with it, or that it's right; but you, the consumer of this product, agreed to those terms when you made your account and downloaded and installed the game.
Read the ToS.