For logistical reasons, your order may be delivered in several parcels.
It is possible that when you placed your order, another customer may have ordered the same product at the same time. Should only one product be available, only one customer will be able to receive their complete order.
We do restock regularly to cover any shortages. So once you receive part of your order, the second part should be with you soon. However, you should also be aware of the possibility that the product may no longer be available at all.