NullReferenceException at GetMapsError

I got this error

Failed to call hook 'SignMapChatCommand' on plugin 'SignMap v1.0.0' (NullReferenceException: Object reference not set to an instance of an object)
  at Oxide.Plugins.SignMap.GetMaps () [0x00000] in <d2e6a020db794ed2897955aa6fb1606c>:0 
  at Oxide.Plugins.SignMap.HandleGen (BasePlayer player, System.String[] args) [0x002da] in <d2e6a020db794ed2897955aa6fb1606c>:0 
  at Oxide.Plugins.SignMap.SignMapChatCommand (BasePlayer player, System.String cmd, System.String[] args) [0x000dd] in <d2e6a020db794ed2897955aa6fb1606c>:0 
  at Oxide.Plugins.SignMap.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x0023a] in <d2e6a020db794ed2897955aa6fb1606c>:0 
  at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00079] in <3e46d2a997e94a3cb08cf065508cd483>:0 
  at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x000d8] in <1fe782f4b27a43ae85d29ebb2d56c007>:0 
  at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <1fe782f4b27a43ae85d29ebb2d56c007>:0
(06:15:12) | Failed to call hook 'SignMapChatCommand' on plugin 'SignMap v1.0.0' (NullReferenceException: Object reference not set to an instance of an object)
  at Oxide.Plugins.SignMap.GetMaps () [0x00000] in <d2e6a020db794ed2897955aa6fb1606c>:0 
Can you please confirm you have the RustMapApi plugin dependency installed?
Sorry my error i forgot to add RustMapApi 
Failed to call hook 'SignMapChatCommand' on plugin 'SignMap v1.0.3' (NullReferenceException: Object reference not set to an instance of an object)
  at Oxide.Plugins.SignMap.GetMaps () [0x00000] in :0
at Oxide.Plugins.SignMap.HandleGen (BasePlayer player, System.String[] args) [0x002da] in :0
at Oxide.Plugins.SignMap.SignMapChatCommand (BasePlayer player, System.String cmd, System.String[] args) [0x000dd] in :0
at Oxide.Plugins.SignMap.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x0023a] in :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 :0
at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in :0

Do you have RustMapsApi installed as it's a required plugin?

As mentioned in the Title....
Pls Update this

What needs updating?

Hey , i dont now. It doesnt work for me.

Failed to call hook 'SignMapChatCommand' on plugin 'SignMap v1.0.3' (NullReferenceException: Object reference not set to an instance of an object)

at Oxide.Plugins.SignMap.GetMaps () [0x00000] in <fcca344b96cf4dc294e3ac6c6259471a>:0

at Oxide.Plugins.SignMap.HandleMaps (BasePlayer player) [0x0001f] in <fcca344b96cf4dc294e3ac6c6259471a>:0

at Oxide.Plugins.SignMap.SignMapChatCommand (BasePlayer player, System.String cmd, System.String[] args) [0x000d1] in <fcca344b96cf4dc294e3ac6c6259471a>:0

at Oxide.Plugins.SignMap.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x0023a] in <fcca344b96cf4dc294e3ac6c6259471a>: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 <50629aa0e75d4126b345d8d9d64da28d>:0

at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <50629aa0e75d4126b345d8d9d64da28d>:0

Do you have the Rust Maps API plugin installed?

Damm ...
depends on