Issue loading textures from a texture-pack in my Minecraft world.

I'm currently in the process of creating a texturepack for Minecraft 1.15.2, but I've encountered an issue I'm not quite sure how to fix. While I was testing my acacia door texture, it loaded perfectly in my hand, yet in the world it shows up as the default Minecraft texture? I've tried everything I could think of to fix this, but I can't seem to get around it. I've re-textured the vanilla texture pixel-by-pixel in Paint.net, I've switched patch versions (1.15.2 to 1.15 to 1.15.1) and clients (from the Badlion Client to the regular Minecraft client). I've also double-checked my pack.mcmeta file and I've both used and not used Optifine. I'm clueless. Any help would be much appreciated.
Note: I've been texturing the top and bottom block textures, not just the item itself, and I ensured they both had the correct names.
EDIT: I fixed it. Turns out I had its 'png's capitalized. I feel dumb now lol