What to do if I no longer need my ZBrush licence?

I have a ZBrush licence that I no longer need. Please advice me what to do with that?

It looks a little bit strange, since it’s your first post and it’s not edited. The title says 450 and the post 600USD. Which brings me to my second question. You ask for USD, so in what country do you live? To my knowledge, if it’s no in the European Union, you are not allowed to sell it.

Sorry for the confusion .
I am from Canada.
I want to sell my zbrush for 600 Canadian Dollar. That would be equivalent to 450 US Dollars.
i will correct my post.
Thank you for your reply.

Please see https://support.pixologic.com/Knowledgebase/Article/View/60/0/license-transfers