I'm getting a similar problem. Whenever I type in /kit to bring up the GUI, I get this in console:

Failed to call hook 'cmdChatKit' on plugin 'Kits v3.2.93' (NullReferenceException: Object reference not set to an instance of an object)

at Oxide.Plugins.Kits.GetKitData (System.UInt64 userID, System.String kitname) [0x00000] in <aeafd60c1bfe4edfb326e1713d7a213e>:0

at Oxide.Plugins.Kits.CreateKitEntry (BasePlayer player, Oxide.Game.Rust.Cui.CuiElementContainer& element, System.String panel, System.Single[] pos, System.String entry) [0x00026] in <aeafd60c1bfe4edfb326e1713d7a213e>:0

at Oxide.Plugins.Kits.RefreshKitPanel (BasePlayer player, System.UInt64 guiId, System.Int32 page) [0x001de] in <aeafd60c1bfe4edfb326e1713d7a213e>:0

at Oxide.Plugins.Kits.NewKitPanel (BasePlayer player, System.UInt64 guiId) [0x00022] in <aeafd60c1bfe4edfb326e1713d7a213e>:0

at Oxide.Plugins.Kits.cmdChatKit (BasePlayer player, System.String command, System.String[] args) [0x0001a] in <aeafd60c1bfe4edfb326e1713d7a213e>:0

at Oxide.Plugins.Kits.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x0102a] in <aeafd60c1bfe4edfb326e1713d7a213e>:0

at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00079] in <9affce1cd15c4ec183941adef8db1722>:0

at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x000d8] in <4452f821def6406d834e4149849fe7ea>:0

at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <4452f821def6406d834e4149849fe7ea>:0