Purchase Order DropShipLocation loaded with Warehouse BPartner Location

I create a Purchase Order and chose a BusinessPartner with Location in Finnland the tax on Positions is correct set to 0%. If the Purchase Order is completed the Invoice Disposition is created. This Invoice Dispositions are created with different Tax, because the Tax finding depends on DropShip Location set on Purchase Order (this is set with the Location from Warehouse Location and this is my org). If I now create an invoice with Invoice Disposition i get wrong tax on invoice.
How can I solve this Situation?

Thanks for help