Usually when you see this type of error it is because you are trying to insert a value for a key column that already exists. Key columns are meant to be unique, so it will not allow you to insert a record that duplicates a key column value.
I looked at your inserts and it does not seem that you are inserting the id for the table which is the most common cause of this issue. Based on what I see on your page it would seem that you have set one of the columns you are inserting into as a key column for the table, thus not allowing any duplicate entries for that field. If you can post back with an export of the db structure in .sql format I can take a look and compare it to the inserts that you have on the page to determine if this is the problem.