Twitter link points to @addthis?????

When someone wants to share a blog post via twitter, the url etc points to the @addthis twitter account. The twitter link looks like this: *postname*! *URL* via @addthis

how can i change the @addthis to my own twitter account? i tried to edit the advanced sitting and add this under the twitter template: {{title}} – {{lurl}} – via @dailylolblog

but it STILL shows the old link and @addthis.

any ideas?