Issue with importing premade armor textures? **SOLVED**

Hello! 

This is my first post here, and I am still working on my first mod. Sorry in advance if this is a silly question, I've looked around the forums and couldn't find anything with this exact issue. 

I have custom armor textures I want to import as resources, but when I try to do so (workspace -> resources -> texture files -> import textures -> import armor texture), I get this window: 

Which I understand - I know armor textures need two layers - but when i click on the "..." to retrieve the file...

The folder with all of my armor textures appears empty (theres 20+ files in this folder) - all of them are PNGs, saved with unique names (not just *layer_1*.png), correct dimensions, etc. It seems like the software itself is looking for "Armor layer 1 texture files" instead of pngs, jpegs, etc... and it won't let me just switch to "all files" - that's the only option. Does anyone know how to fix this? 

Thanks in advance! 

EDIT: I realized i made a silly mistake by not including *layer_1*/etc in the name of the file. Thank you to Klemen for posting this answer!