Stolen steam account link

[NukedN54]

I just downloaded plutonium and it says that my account is already linked. This is false. I own the account. How do i have my account unlinked from who ever stole my login?

[P_McNewHold]

Is it your actual Steam account, or did you bought such Steam account elsewhere ? If it's the latter, it's your fault for trying to derogate the Steam ToS.