I am trying to establish communication between "RoboDK" and "Unity." I have followed all the steps in the following video (

;t=848s). However, when running "Unity," I encounter the following errors:

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

game4automation.RoboDKTarget.Start () (at Assets/game4automation/private/Interfaces/RoboDK/RoboDKTarget.cs:22)

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

game4automation.RoboDKInterface.InitAxis () (at Assets/game4automation/private/Interfaces/RoboDK/RoboDKInterface.cs:383)

game4automation.RoboDKInterface.Start () (at Assets/game4automation/private/Interfaces/RoboDK/RoboDKInterface.cs:349)

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

game4automation.RoboDKInterface.UpdateAxisPosition () (at Assets/game4automation/private/Interfaces/RoboDK/RoboDKInterface.cs:397)

game4automation.RoboDKInterface.CommunicationThreadUpdate () (at Assets/game4automation/private/Interfaces/RoboDK/RoboDKInterface.cs:528)

game4automation.InterfaceThreadedBaseClass.CommunicationThread () (at Assets/game4automation/private/Interfaces/InterfaceThreadedBaseClass.cs:92)

System.Threading.ThreadHelper.ThreadStart_Context (System.Object state) (at :0)

System.Threading.ExecutionContext.RunInternal (System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, System.Object state, System.Boolean preserveSyncCtx) (at :0)

System.Threading.ExecutionContext.Run (System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, System.Object state, System.Boolean preserveSyncCtx) (at :0)

System.Threading.ExecutionContext.Run (System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, System.Object state) (at :0)

System.Threading.ThreadHelper.ThreadStart () (at :0)

UnityEngine.<>c:b__0_0(Object, UnhandledExceptionEventArgs)

I'm not sure where these errors might be coming from. Could someone help me resolve them?