There are a few different ways to enter and manage AP invoices in AX. In AX2012 the product concepts where changed as well the category concepts were introduced so you can use purchase orders for non inventory based purchase more easily. This videos gives an overview of the PO based invoices.
This video was recorded on AX2012 R2 but the same concepts apply to any version of AX2012.
Please can you let me know how to split one purchase order into two because the supplier as issued two invoices.
In this case you probably don’t want to split the purchase order if that was how it was originally placed to the supplier so you want to keep that record the same. But you can enter multiple invoices and pick what you are matching again. Here are a couple of quick examples.