IP Ban, but why?

Hello, My IP got banned but I don't know why.

I was trading on Sythe.org and all went well.
When I wanted to vouche for the guy I was banned.
Cause I can't log-on with the messenge:

Sorry. The administrator has banned your IP address. If you feel that your IP address should NOT be banned, you may contact the administrator here, or ask someone to post in the Dispute Forum on your behalf.

The day before I got banned my Sythe.org account got hacked but short after that I was able to recover my account with the secret question.
In the main time I don't know what the hacker did with my account but I got
the blame cause my IP is banned for ever.

Can you please unblock my IP so I can trade my rs accounts/buying mills/buying pins the things I'd like to do on Sythe and can't do anymore.

My IP: 82.92.80.34 - The Netherlands

Thanks!