Yoast duplicates title tags

My website: http://bit.ly/H4TI7C

Searching for the reason of traffic drop, I found inside my webmaster tool,a huge number of duplicate title tags (1700) and meta description (1050)..

Basically, errors are showing /0/ at the end or sometimes the same title twice written

Screenshot : http://i43.tinypic.com/s26v87.jpg

Pls..how to fix this

http://wordpress.org/extend/plugins/wordpress-seo/