Why skins dont show?

So I openned a few crates and got some skin, but they dont show. I use 1.12 with mods
I cant upload pic for some reason but there is a skin menu and i have a scythe visuals(they work fine), but i dont have visuals of hat and relic. Its like a red X and thats all

 

That last sentence of yours was the key: your resource pack is outdated. Update it by setting your resource pack to default, and enabling Wynn's custom one in the server editing menu. Next time you enter a world, it'll load automatically.

 

How do I enable that?

 

Click on Wynn in the server menu, select the "Edit" button in the menu at the bottom of the screen, then click on the resource pack button until it says "Resource packs: enabled", or something like that.