Oops... looks like the spiders padded through here
Add products to your cart and remove them from here Lets buy❓ Why is the attack damage missing from my items?
#Answer
The lobby items are built with every hide flag on, so the lines Minecraft normally adds under the name — attack damage, attack speed, armour, unbreakable, what the item can be placed on — are all hidden. Only the name and the lore you wrote are shown.
That is deliberate. A compass or a sword sitting in the hotbar as a button looks wrong with a block of combat statistics under it.
The switch is hide-enchantments in lobby-items.yml:
hide-enchantments: true
Turning it off brings back the enchantment lines, and only those. The attribute lines stay hidden either way, so there is currently no way to show attack damage on a lobby item.
This applies to the hotbar items. Items inside a menu use hide-attributes instead, which starts off, so a sword in a menu does show its statistics until you turn that on.
The full list of what each option covers is on Item Options.