So while playing modded minecraft on 1.12.2 with 59 mods have i found this bug that makes it the armour not move with the player (as seen with the picture), i dont know what it causes.
https://photos.google.com/search/_tra_/photo/AF1QipPNDz0p2v-Eofw3zMDQ6GQRTwRiQPwgxk89U5Bq