重新进入AR场景时Vuforia崩溃

Question

问候， 我遇到一些问题，当我再次进入AR场景时，出现了这个错误。并且相机关闭。 有人遇到过这个问题吗？

Exception in callback: System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> UnityEngine.MissingReferenceException: The object of type 'SetupImageTarget' has been destroyed but you are still trying to access it.
Your script should either check if it is null or you should not destroy the object.
  at (wrapper managed-to-native) UnityEngine.MonoBehaviour.IsObjectMonoBehaviour(UnityEngine.Object)
  at UnityEngine.MonoBehaviour.StartCoroutine (System.Collections.IEnumerator routine) [0x00014] in <58a34b0a618d424bb5fc18bb9bcdac20>:0 
  at SetupImageTarget.CreateImageTargetFromSideloadedTexture () [0x0005f] in D:\UnityProject\PopulAR_Dummy - Backup - v2\Assets\SetupImageTarget.cs:76 
  at (wrapper managed-to-native) System.Reflection.MonoMethod.InternalInvoke(System.Reflection.MonoMethod,object,object[],System.Exception&)
  at System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x00032] in <437ba245d8404784b9fbab9b439ac908>:0 
   --- End of inner exception stack trace ---
  at System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x00048] in <437ba245d8404784b9fbab9b439ac908>:0 
  at System.Reflection.MethodBase.Invoke (System.Object obj, System.Object[] parameters) [0x00000] in <437ba245d8404784b9fbab9b439ac908>:0 
  at System.Delegate.DynamicInvokeImpl (System.Object[] args) [0x000e7] in <437ba245d8404784b9fbab9b439ac908>:0 
  at System.MulticastDelegate.DynamicInvokeImpl (System.Object[] args) [0x00008] in <437ba245d8404784b9fbab9b439ac908>:0 
  at System.Delegate.DynamicInvoke (System.Object[] args) [0x00000] in <437ba245d8404784b9fbab9b439ac908>:0 
  at Vuforia.DelegateHelper.InvokeDelegate (System.Delegate action, System.Object[] args) [0x0000f] in <c6d6035d26434a6a94f7179ae382aebf>:0 
UnityEngine.Debug:LogError(Object)
Vuforia.DelegateHelper:InvokeDelegate(Delegate, Object[])
Vuforia.DelegateHelper:InvokeWithExceptionHandling(Action)
Vuforia.VuforiaARController:StartAfterInitializationCompleted()
Vuforia.VuforiaARController:Start()
System.Delegate:DynamicInvoke(Object[])
Vuforia.DelegateHelper:InvokeDelegate(Delegate, Object[])
Vuforia.DelegateHelper:InvokeWithExceptionHandling(Action)
Vuforia.VuforiaBehaviour:Start()