Hello i have 2 console error 
The first :

Failed to call hook 'cmdChatZone' on plugin 'ZoneManager v3.0.91' (NullReferenceException: Object reference not set to an instance of an object)

at Oxide.Plugins.ZoneManager.SendMessage (BasePlayer player, System.String message, System.Object[] args) [0x00030] in <c9619d2bb8e24d2c957c17cad0afaa56>:0

at Oxide.Plugins.ZoneManager.cmdChatZone (BasePlayer player, System.String command, System.String[] args) [0x0003c] in <c9619d2bb8e24d2c957c17cad0afaa56>:0

at Oxide.Plugins.ZoneManager.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x03986] in <c9619d2bb8e24d2c957c17cad0afaa56>:0

at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00079] in <3606d2af539c45e4b5c61658e6a8b307>:0

at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x000d8] in <c2afd8354b8b4f3ca451cf5a1aa111c3>:0

at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <c2afd8354b8b4f3ca451cf5a1aa111c3>:0

The second : 

NullReferenceException: Object reference not set to an instance of an object

The second error occurs when I enter a pvp zone. entering the dome area and leaving the area.

Thanks for the help I can get