D365 - Fixed asset description

Hi,

I am using D365 8.1. In the PO invoice form, Ima choosing a procurement category where I am overriding the text field to enter the real item description, which is selected to be as Fixed assets = Yes,

When it is posted, I am expecting to see that the Fixed asset description should be coming from the 'text filed' on the pO line item, however I see the procurement category description.

Sam