Please be sure to check your spam folder. We also have realized that some email providers (Verizon, Sbcglobal.net, Freenet.de, Comcast, etc.) have blocked our domain (kerbalspaceprogram.com) and IP Address due to their strict incoming email rules. They added us to their spam lists, so you won’t receive an email from us. Send an email to KSP Support explaining your problem. They will manually reset your password and ask you to change your KSP Store Account email address. If you are using an account from Gmail, Hotmail, Yahoo, or something similar, you might want to check your spam folder before asking for help, password-recovery emails usually end up in the spam folder.
If you still need help, you can submit a support ticket here.