Can't Export PNG with a Transparent Background - Photoshop

I'm so confused and can't figure out what I'm doing wrong. 

I'm trying to create digital tape with pattern overlays and then export to a PNG in Photoshop. This digital tape has a lower opacity and a transparent background. However, anytime I try to export as a PNG a white background is added. The transparency box is checked in the export settings and the background for the artboard is transparent. It looks transparent in the export screen but never actually exports with the transparent background. I've searched for a solution but haven't found anything that works.

Any ideas?