This is what showed up on console.Bug
Failed to call hook 'RestoreCommand' on plugin 'SignArtist v1.4.0' (NullReferenceException: Object reference not set to an instance of an object)
at Oxide.Plugins.SignArtist.HasPermission (BasePlayer player, System.String perm) [0x00000] in <7d19b376636247e5b072216a028bd94f>:0

at Oxide.Plugins.SignArtist.RestoreCommand (Oxide.Core.Libraries.Covalence.IPlayer iplayer, System.String command, System.String[] args) [0x0000c] in <7d19b376636247e5b072216a028bd94f>:0

at Oxide.Plugins.SignArtist.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x003aa] in <7d19b376636247e5b072216a028bd94f>: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
Failed to call hook 'RestoreCommand' on plugin 'SignArtist v1.4.0' (NullReferenceException: Object reference not set to an instance of an object)
at Oxide.Plugins.SignArtist.HasPermission (BasePlayer player, System.String perm) [0x00000] in <2e8abf7c31b946a4bb2020f636ca2089>:0

at Oxide.Plugins.SignArtist.RestoreCommand (Oxide.Core.Libraries.Covalence.IPlayer iplayer, System.String command, System.String[] args) [0x0000c] in <2e8abf7c31b946a4bb2020f636ca2089>:0

at Oxide.Plugins.SignArtist.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x003aa] in <2e8abf7c31b946a4bb2020f636ca2089>: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