Failed to call hook 'OnPlayerCommand' on plugin 'TimedCommandBlocker v1.3.1' (ArgumentNullException: Value cannot be null.

And the command is not being blocked.

{
  "Enable logging": true,
  "Chat steamID icon": 0,
  "Сommand color": "#ffffff",
  "Remaining blocking time color": "#FFA500",
  "Blocked commands (command: seconds)": [
    {
      "Command": "Blocked for 1 day",
      "BlockDuration": 86400.0
    },
    {
      "Command": "Blocked permanently",
      "BlockDuration": -1.0
    },
    {
      "clan": "Blocked permanently",
      "BlockDuration": -1.0
    },
    {
      "Command": "Not blocked",
      "BlockDuration": 0.0
    }
  ]
}

Unloaded plugin Timed Command Blocker v1.3.1 by MON@H
Loaded plugin Timed Command Blocker v1.3.1 by MON@H
Failed to call hook 'OnServerCommand' on plugin 'TimedCommandBlocker v1.3.1' (ArgumentNullException: Value cannot be null.
  at System.String.StartsWith (System.String value, System.StringComparison comparisonType) [0x00003] in <eae584ce26bc40229c1b1aa476bfa589>:0 
  at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00079] in <60c318df79ed41688ea59335e48d61ad>:0 
  at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x000d8] in <dfcb48ea05694263bbc08e62a39c274c>:0 
  at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <dfcb48ea05694263bbc08e62a39c274c>:0 

Never mind I found the problem I just had to read that post.

Yes leason learned again, read before you post

https://umod.org/community/timed-command-blocker/21580-block-clan-commands