Scammer Seqos?

Hi. On the 25th August 2014 i bought an a account from a username called "Seqos" - http://www.sythe.org/members/420098-seqos.html
Played for like 2 weeks and tried to log on on the third week, but says 'wrong username or password' and the email was also changed, so i didn't know what to do and i found this thread. I don't know how to prove this, but the best idea i though that Seqos, the last owner of the account, add's me again in skype and maybe helps me to recover the account back with the old rec's and stuff he didn't gave to me.
The account sell page - http://www.sythe.org/runescape-2007-mains/1748706-selling-lvl-97-starter-main.html

Thank you, hope you can help me.
//So i got the account locked and now Jagex asks me to do an a recovery test.

 

User has 24 hours to reply and get something going in regards to recovering your account. He is responsible to sell a safe account.

 

User banned.