I bought a Traktor Kontrol s2 board secondhand and am not in contact with the original owner. I'm not sure if it's been registered, but either way I don't have the serial number or the original owner's contact, so I can't figure out how to register it. I have tried contacting the service center and no one has answered my multiple requests. I am so confused what the work around is, without getting in contact with an agent who can register it without the serial number or something. please help me!!!!