I am the person that will be helping you today.
If it is blacklisted now, that means that the person who owned it before reported it as being stolen. The person who sold it to you may have stolen it or found it somewhere. The original owner just have called and reported it stolen soon after you purchased it. There is no way to take it off the blacklist. You may wish to contact your local authorities regarding this case and create a police report or you may wish to contact the seller, if you feel comfortable doing so.
I will be standing by.