Move posts from one tabel to another with checkboxes in HTML DB

Question

I wish to replace the checked rows from one table to another with a PL/SQL statement.
When I wish to replace one row, there is no problem. But when I wish to replace two or more I get an error ORA-00001: unique constraint (HTMLDB_ERASMUS.SYS_C0042823) violated.
The only unique constraint in my table is the primary key ID, witch is generated with a sequence, so normally there is never twice the same value for an ID.
Can someone help me here, please?
Here is my code
DECLARE     
lv_i NUMBER :=1;
lv_ID add_post.ID%TYPE;
lv_auteur add_post.auteur%TYPE;
lv_titel add_post.titel%TYPE;
lv_community add_post.community%TYPE;
lv_rating add_post.rating%TYPE;
lv_description add_post.description%TYPE;
CURSOR move_posts iS
SELECT ID, auteur, titel, community, rating, description
FROM add_post
WHERE ID = HTMLDB_APPLICATION.G_F01(lv_i);
BEGIN
FOR lv_i IN 1..HTMLDB_APPLICATION.G_F01.count LOOP
OPEN move_posts;
FETCH move_posts INTO lv_ID, lv_auteur, lv_community, lv_titel, lv_rating, lv_description;
INSERT INTO wouter_published_posts VALUES (lv_ID, lv_auteur, lv_community, lv_titel, lv_rating, lv_description);
DELETE FROM add_post WHERE ID = HTMLDB_APPLICATION.G_F01(lv_i);
--EXIT WHEN move_posts%NOTFOUND;
COMMIT;
CLOSE move_posts;
END LOOP;
END;

Answer 1

That should not be necessary because I get the value of ID out of another table, where I generate ID with a sequence..
So normally it should just tranfer that row from one table to another. But it doesn't !
Knowing that I cannot create a row in the table wouter_published_posts(I can just move rows from the add_post table to the wouter_published_posts table), It should be inpossible that twice the ID appears. But yet he keeps trowing errors...
help me, please