so is there something i am doing wrong within the code ?
So your new Item stack, should really be a ItemStackSnapshot and then when you want to use it as an item you build a new instance of the item, otherwise everyone is sharing the same item.
As for this, have you got a log of the server?
i have got the issue fixed as it was an issue with the items i had in my inventory i was using in the crafting recipe
but i will look into using the ItemStackSnapShot