Problem/Bug Problem with PEX (What's wrong?)

Code:

groups:
  Peasant:
    options:
      rank: '3000'
      rank-ladder: Member
      default: true
      prefix: ''
    permissions:
    - essentials.signs.use.*
    - essentials.pay
    - essentials.balance
    - essentials.signs.use.buy
    - essentials.signs.use.enchant
    - essentials.signs.use.heal
    - essentials.signs.use.repair
    - essentials.list
    - essentials.msg
    - easywarp.command.warp
    - nofalldamage.*
    - essentials.suicide
    - easywarp.command.listwarps
    - killrewardessentials.canbekillrewarded
    - kingkits.kits.peasant
    - kingkits.kit.use
    - pp.use
  Archer:
    options:
      rank: '2000'
      rank-ladder: Member
      default: false
      prefix: ''
    permissions:
    - kingkits.kits.archer
    inheritance:
    - peasant
  Merchant:
    options:
      rank: '1000'
      rank-ladder: Member
      default: false
      prefix: ''
    permissions:
    - kingkits.kits.merchant
    inheritance:
    - peasant
    - archer
  Mage:
    options:
      rank: '900'
      rank-ladder: Member
      default: false
      prefix: ''
    permissions:
    - kingkits.kits.mage
    inheritance:
    - peasant
    - archer
    - merchant
  Thespian:
      rank: '800'
      rank-ladder: Member
    options:
      default: false
      prefix: ''
    permissions:
    - kingkits.kits.thespian
    inheritance:
    - peasant
    - archer
    - merchant
    - mage
  Constable:
    options:
      rank: '700'
      rank-ladder: Member
      default: false
      prefix: ''
    permissions:
    - kingkits.kits.constable
    inheritance:
    - peasant
    - archer
    - mage
    - merchant
    - thespian
  Thane:
    options:
      rank: '600'
      rank-ladder: Member
      default: false
      prefix: ''
    permissions:
    - kingkits.kits.thane
    inheritance:
    - peasant
    - archer
    - mage
    - merchant
    - thespian
    - constable
  Armiger:
    options:
      rank: '500'
      rank-ladder: Member
      default: false
      prefix: ''
    permissions:
    - kingkits.kits.armiger
    inheritance:
    - peasant
    - archer
    - merchant
    - mage
    - constable
    - thane
    - thespian
  Muskateer:
    options:
      rank: '400'
      rank-ladder: Member
      default: false
      prefix: ''
    permissions:
    - kingkits.kits.muskateer
    inheritance:
    - peasant
    - archer
    - mage
    - merchant
    - thane
    - thespian
    - constable
    - armiger
  Baron:
    options:
      rank: '300'
      rank-ladder: Member
      default: false
      prefix: ''
    permissions:
    - kingkits.kits.baron
    inheritance:
    - peasant
    - archer
    - mage
    - merchant
    - muskateer
    - constable
    - thane
    - thespian
    - armiger
  Duke:
    options:
      rank: '200'
      rank-ladder: Member
      default: false
      prefix: ''
    permissions:
    - kingkits.kits.duke
    inheritance:
    - peasant
    - archer
    - mage
    - merchant
    - muskateer
    - thespian
    - thane
    - armiger
    - constable
    - baron
  Warhead:
    options:
      rank: '100'
      rank-ladder: Member
      default: false
      prefix: ''
    permissions:
    - kingkits.kits.warhead
    inheritance:
    - peasant
    - archer
    - mage
    - merchant
    - muskateer
    - thane
    - thespian
    - armiger
    - duke
    - constable
    - baron
schema-version: 1
users:
  73e29c61-6c97-4788-bd3c-f558f109d627:
    group:
    - Peasant
    options:
      name: Launcher_One

This is my rank ladder for my kitpvp server. everything was fine until i added the rank and rank-ladder option. what did i do wrong?

 

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