Problem in the discount condition in the order item

Good morning, I have a problem that is as follows:

Within a sales order there are 2 discount conditions, both of which are set to "header". When I create the sales order and I type these 2 conditions in the header they are automatically reproduced in the items.

However, if I create a sales order with reference to an invoice or an order that has these conditions in the header, the new sales order only takes these two conditions for the header and not for the items. Can anybody help me?