Failed to initialize plugin 'SteamChecks v3.0.4' (InvalidCastException: Null object can not be converted to a value type.)
at System.Convert.ToType (System.Object value, System.Type conversionType, IFormatProvider provider, Boolean try_target_to_type) [0x00000] in <filename unknown>:0
at System.Convert.ChangeType (System.Object value, System.Type conversionType) [0x00000] in <filename unknown>:0
at Oxide.Core.Configuration.DynamicConfigFile.ConvertValue (System.Object value, System.Type destinationType) [0x00000] in <filename unknown>:0
at Oxide.Core.Configuration.DynamicConfigFile.ConvertValue[Boolean] (System.Object value) [0x00000] in <filename unknown>:0
at Oxide.Core.Configuration.DynamicConfigFile.Get[Boolean] (System.String[] path) [0x00000] in <filename unknown>:0
at Oxide.Plugins.SteamChecks.InitialiseConfig () [0x00000] in <filename unknown>:0
at Oxide.Plugins.SteamChecks.Init () [0x00000] in <filename unknown>:0
at Oxide.Plugins.SteamChecks.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x00000] in <filename unknown>:0
at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00000] in <filename unknown>:0
at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x00000] in <filename unknown>:0
at Oxide.Core.Plugins.CSPlugin.HandleAddedToManager (Oxide.Core.Plugins.PluginManager manager) [0x00000] in <filename unknown>:0

I got this error after I had to reload the plugin, 
So can someone fix this, please?

Looks like an error in your config file, not an error with the plugin. Something wasn’t edited correctly in your config.