i try to delete contacts in kaddressbook but i cant . I dont have any error message but after delete it the contact is still there

Hm, first I'd make sure that only one address book source is being read, not two or more.

That is a known bug, here is a report that I made and a workaround: https://bugs.kde.org/show_bug.cgi?id=230260

There's a distinct possibility that you are seeing the cached entry. How long does it stay cached? I really don't know. Do they persist through logout, reboot, etc?

Just to test, I have just deleted a contact in Personal Contacts addressbook and it disappeared immediately. Maybe this is a bug in the version you're using?

after reboot i cant reproduce it anymore, i am able to delete a contact now

Good - it probably was just cache, then