Hi,
i have currently one existing npc and i wanted to reset it. So i tried the command /npc_reset.
This is the output:

Failed to call hook 'cmdChatNPCReset' on plugin 'HumanNPC v0.3.52' (ArgumentException: An item with the same key has already been added. Key: snowballgun)
  at System.Collections.Generic.Dictionary`2[TKey,TValue].TryInsert (TKey key, TValue value, System.Collections.Generic.InsertionBehavior behavior) [0x000c1] in <eae584ce26bc40229c1b1aa476bfa589>:0 
  at System.Collections.Generic.Dictionary`2[TKey,TValue].Add (TKey key, TValue value) [0x00000] in <eae584ce26bc40229c1b1aa476bfa589>:0 
  at Oxide.Plugins.HumanNPC.OnServerInitialized () [0x00117] in <414830f2aba24c828d77ea841ccd64d7>:0 
  at Oxide.Plugins.HumanNPC.cmdChatNPCReset (BasePlayer player, System.String command, System.String[] args) [0x00068] in <414830f2aba24c828d77ea841ccd64d7>:0 
  at Oxide.Plugins.HumanNPC.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x0122f] in <414830f2aba24c828d77ea841ccd64d7>:0 
  at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00079] in <31122a27a2414cd799150f8677cf39d4>:0 
  at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x000d8] in <0fbce81d88d64454b3e7abb24df7026b>:0 
  at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <0fbce81d88d64454b3e7abb24df7026b>:0​

The npc is still there