The settings made in the shipment plugin
Order with only briefpost gratis, goes wrong
Order with briefpost gratis and stevia briefpost. Goes well
Order with all three sending classes, briefpost gratis, stevia briefpost and pakket post, goes well
If I add only products of the stevia briefpost sending class or the pakket post sending class, it all goed wright.
Basicly it goes wrong on the free shipping class, briefpost gratis