help cydia problem with many errors

Hi
2 weeks ago I started to have this problem
when I start the cydia it opens with some error.
I have wrote down them so I could share with you all.

the first error message.
unable to parse package file /var/lib/apt/lists/xsellize.com cydia

second error
gpg error: http://xsellize.com./release:the following signatures were invalid:Nodata 1 nodata 2

after all errors are gone my installed packages are invisible and cant install anything from cydia. tryed to install openssh. but says cannot locate the package

would be greatful if someone could help mee.
bs