Items Disappearing

Im the realm owner and this bug doesn't seem to affect me. But its affecting the other members. Their items ( usually tools & weapons, like pickaxes and swords, a bow, shield ) have been disappearing. This usually happens in a few instances, 1. Right after crafting, when they suddenly jump or walk away fast from the crafting the table, it would disappear. Sometimes they are holding that particular tool and sometimes its disappears from the hotbar. 2. Also happens when they press and hold, ie use the tool to mine or cut trees or kill  mobs it disappears from their hand.3. Right after enchanting the item, once they hold it, it disappears.  We have members playing from an Ipad, Android mobile and Windows PC. Its affecting all of them equally. We don't have any screenshots to support as evidence because the item is gone and there doesn't seem to be any other pattern other than holding or using that tool/ weapon. Our realm is new, not even a month old yet.