Random animation and InvokeRepeating

I have wrote a code to change idle animation when there are no actions don't happen during 5 seconds:

 private string [] idleArray = new string[]{"idle&quot", "idle2', "idle3", "idle4", "idle5", "idle6"};
 
  void Idle()
  {
  animation.CrossFade("idle");
  if(!IsInvoking("ChangeIdleAnimation"))
  InvokeRepeating("ChangeIdleAnimation", 5.0f, 5.0f);
  }
  
  void ChangeIdleAnimation()
  {
  string idleAnimation = idleArray[Random.Range(1,5)];
  
  animation.CrossFade(idleAnimation);
  }
  
  void StopRandomIdleAnimation()
  {
  if(IsInvoking("ChangeIdleAnimation"))
  {
  CancelInvoke("ChangeIdleAnimation");
  }
  }
  
  
  void Running()
  {
  StopRandomIdleAnimation();
  animation.CrossFade("run");
  }

But the idle animation doesn't change, in spite of that method ChangeIdleAnimation() invokes every 5 seconds. Where is a mistake? enter code here