How do I remove white line from graphic to make it transparent?

I am creating a vector for a t-shirt and want it to be a single-color graphic. How do I remove the white line to be transparent? I’ve made all strokes outlines and tried subtracting from the black shapes but it doesn’t work the way I wanted.

I am using this as a T-Shirt graphic so need to remove, not apply filter like multiply on artwork.

Any recommendations?

Figma Graphic

Figma Layers

Tshirt Mockup (desired look)