WordPress MU

hi,
I have inserted different pages per SQL INSERT into one of my wp_posts tables. The pages I can see in the overview of the admin panel, but the permalink to the pages is not working.

for example:

Page with title: 'About Us' and permalink /about-us
is not found and I am getting the URL in the browser:

http://blogdomain.de//about-us/
instead of
http://blogdomain.de/about-us/

as I found the guid in the wp table is wrong. But I am using the wp_insert_post function