Advanced Excel- Array formula issue

Hey EXcel Geniuses,

NOTE: All comments below refer to the Dropbox file (too large for the uploader) here is a link to download:https://www.dropbox.com/s/e1sguzb5kq...ject.xlsx?dl=0 . I have been working on an inventory purchase order creation form for a while and it used to work until I started creating larger lists. For some reason, with the attached PO creator - when I place a Qty anywhere below 1980 on the drum title sheet, (which feeds the Order Form sheet) The Array formula used to populate the order page is

{=IFERROR(INDEX(complete!$A$2:$A$2024, SMALL(IF(complete!$G$2:$G$2024>0, ROW($H$5:$H$1982)-ROW($H$5)+1),ROWS($A$3:$A3))),"")}

The attached document opens to the order form. If you go to the Drum Titles tab, you can see the quantities and prices of the items on the Order Form tab. Now place a qty anywhere below row 1980 and voila! the Order form is empty! Can anyone help??

Thanks