Hrrrmm.. can't u get an xchange from the place of purchase?
I might try that but i thought it would it would more efficient to go through them instead. It's just a keycap, not worth sending in for repair.
Message them on Facebook. I got an answer within like half an hour through there.
I know Ducky Keyboards UK have a FB page but it seems i can't message them privately, or should i type directly to their wall?