No I didn’t get it resolved but I know why it stops.
I made one main website and 4 subsites. The posts on the subsites automatically comes on the main site even when they are posted on the administration panel of the subsite.
On the main site, the pagination stops at 5 because there are 21 items posted on this administration module (5 posts per page). So in theory this is correct. But as the other posts from the subsites also come on the main site, I have more than 5 pages.
I used the standard pagination for the main site and the plugin for the subsites (the standard pagination doesn’t work on the subsites …)