better bundle

hey guys, so i do not develop data packs but i have a question about existing one im using a mod/datapack called "better bundle" by nico4play, and in description it says that this mod will increase bundle size to 27 stacks of items, instead of only one, but it doesnt seem to work, i can still only put 1 stack of items in there also it says if i hold a bundle in my off hand and main hand is empty, when clicked on a chest it will insert contents of a bundle into that chest, but it also doesnt work tried to do /reload but still the same im playing on a fabric server (im an admin) on version 1.21.5