so i was using a resource pack and i noticed that the custom heads i had put down were, well messed up and when i took a look at my skin for some reason i had the default skin and the skin was also messed up, when i switched back to the default look, my skin loaded and the custom heads were using the default head, i used a command to get the heads, but when i was last in the world which was a few days ago, the heads were displaying fine and now i go into the world and they won't display, i tried putting them down again and using the command blocks again to see if it would fix it, but they continued to display the default head. i couldn't find this mentioned anywhere else, so i thought i would mention it. (the last image shows what the heads should be showing)