getting this in rcon when i added it 

| Failed to call hook 'OnServerInitialized' on plugin 'EventRandomizer v0.3.1' (KeyNotFoundException: The given key was not present in the dictionary.)
  at System.Collections.Generic.Dictionary`2[TKey,TValue].get_Item (TKey key) [0x0001e] in <ac823e2bb42b41bda67924a45a0173c3>:0 
  at Oxide.Plugins.EventRandomizer.OnServerInitialized () [0x0040c] in <649a560994cf4748a6f08087b547bdc5>:0 
  at Oxide.Plugins.EventRandomizer.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x0017c] in <649a560994cf4748a6f08087b547bdc5>:0 
  at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00079] in <9affce1cd15c4ec183941adef8db1722>:0 
  at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x000d8] in <4452f821def6406d834e4149849fe7ea>:0 
  at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <4452f821def6406d834e4149849fe7ea>:0​

Can you post your config file?

{
  "Event Timers in seconds": {
    "Cargo": {
      "Max": 10800.0,
      "Min": 7200.0
    },
    "Chinook": {
      "Max": 14400.0,
      "Min": 7200.0
    },
    "Helicopter": {
      "Max": 7200.0,
      "Min": 3600.0
    }
  }
}

Merged post

nevermind never deleted orignal config 

Update your config file to this:

{
  "Block Airdrops spawned by the server": true,
  "Block Cargo Ships spawned by the server": true,
  "Block Chinooks spawned by the server": true,
  "Block Patrol Helicopters spawned by the server": true,
  "Event Timers in seconds": {
    "Airdrop": {
      "Max": 3600.0,
      "Min": 3600.0
    },
    "Cargo": {
      "Max": 10800.0,
      "Min": 7200.0
    },
    "Chinook": {
      "Max": 14400.0,
      "Min": 7200.0
    },
    "Helicopter": {
      "Max": 7200.0,
      "Min": 3600.0
    }
  }
}​

i deleted my old config solved