Supplier invoice /PO/ Fixed Asset code part

I raise PO for no-part order for a fixed asset,  when i booked in the supplier invoice do the PO matching everything work fine, but when come to final posting it popped out this error message:

I retrieve the PO and insert the asset ID in the pre-posting.  I thought it would help the final posting of the supplier invoice.  To my naïve the error still there.  

Can anyone shed some light on this?