15:21 [Info] [Electric Fridge] Found box
15:21 [Info] [Electric Fridge] Found heater
15:22 [Error] Failed to call hook 'OnServerShutdown' on plugin 'XPerience v1.7.0' (NullReferenceException: Object reference not set to an instance of an object)
  at Oxide.Plugins.XPerience.OnServerShutdown () [0x0000b] in <c1e9229421fd4682b00a76066a32cf80>:0

  at Oxide.Plugins.XPerience.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x02572] in <c1e9229421fd4682b00a76066a32cf80>:0

  at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00079] in <09575a60985045248bcb43b20faeeb99>:0

  at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x000d8] in <bae5f1223fce49c493b01571c99dce02>:0

  at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <bae5f1223fce49c493b01571c99dce02>:0

15:22 [Info] Unloaded plugin Rust:IO for Oxide v2.17.0 by playrust.io / dcode

is this the crash reason ?

Not the reason