INDEX, MODE, MATCH returning #NA

Don't know how much information I need to provide but here is what I am trying to accomplish. I have a column of "Parts" I want to take the most frequent recurring part and have it populate into a "Most popular parts"

the formula I am using is {=INDEX(D5:D90,MODE(IF(D5:D90<>"",MATCH(D5:D90,D5:D90,0))))}

The formula working fine and giving the intended result. this formula will be running across 12 pages (JANUARY-DECEMBER) and will have a Year To Date Summary page.

What is happening is the #NA that is being generated in the "Most popular parts" on the 11 pages of the non current month is returning a #NA on my summary page.

How could I change this formula so the #NA is not counted, doesn't return as a #NA, and doesn't contributed.