yellow let it mellow is a scammer

First of all i bought 1 pin from him and used it 1 hour later and it worked fine.
Then i bought another pin from him and asked him if hes sure that its working and he said 100% yes i am sure. When i tryid to use it it was invalid.Then i asked him to give me my 1 m back or give me working pin which he declined and started accusing me in that its me scammed him and now i am trying to get another pin for free.
Here is link to his thread http://www.sythe.org/showthread.php?t=256921
and msn convo where is proof he sold first and second pin.