My items won't load? I have no idea why..

So I have tried making mobs and the drops. It worked at the start but suddenly, the main item from the drops stopped loading. These are the items. I've checked countless of times and i still have no idea why.. The rest of the files are right too. These are the items.
NightmareEgg:
Id: 122
Data: 0
Display: '&8NightmareEgg'
Lore:
- 'Used to exchange for a &8Nightmare Easter Egg'
- 'Happy Easter!'
SkyEgg:
Id: 122
Data: 0
Display: '&9SkyEgg'
Lore:
- 'Used to exchange for a...

My items won't load? I have no idea why..