Duplicate Entry Error

[Ms_Gft]

I am just about done with my cart...I am having serious difficulties encountering the error below during the confirmation of the checkout process, if anyone can help me rectify it, it will be much appreciated.

 

Thanks in advance for your help

 

1062 - Duplicate entry '0.0000' for key 2

 

insert into orders_products (orders_id, products_id, products_model, products_name, products_price, final_price, products_tax, products_quantity) values ('24', '66', '', 'YOUR BIRTHDAY', '39.9500', '39.95', '0', '1')

 

[TEP STOP]

[Ms_Gft]

Again everyone this issue is still unresolved for me....when a customer gets to the confirmation the error I listed above comes up, if the customer is unaware and refreshes, it makes then 2 orders, 3, 4....etc depleting stock levels.

 

All help would be greatly appreciated