Problem with enemy moving onto player (Lerpz tutorial)

I'm working on this - https://www.assetstore.unity3d.com/#/content/5087

When player is close to enemy it should start moving. But it's not. I think the problem in simplemove. Because for one frame it moves, but then stops. And not moving until program enters in "while" cycle again. What can be wrong?

 function Attack ()
 {
     isAttacking = true;
     
     if (attackSound)
     {
         if (audio.clip != attackSound)
         {
             audio.Stop();    // stop the idling audio so we can switch out the audio clip.
             audio.clip = attackSound;
             audio.loop = true;    // change the clip, then play
             audio.Play();
         }
     }
     
     // Already queue up the attack run animation but set it's blend wieght to 0
     // it gets blended in later
     // it is looping so it will keep playing until we stop it.
     animation.Play("attackrun");
     
     // First we wait for a bit so the player can prepare while we turn around
     // As we near an angle of 0, we will begin to move
     var angle : float;
     angle = 180.0;
     var time : float;
     time = 0.0;
     var direction : Vector3;
     while (angle > 5 || time < attackTurnTime) 
     {
         time += Time.deltaTime;
         angle = Mathf.Abs(RotateTowardsPosition(target.position, rotateSpeed));
         move = Mathf.Clamp01((90 - angle) / 90);
         
         // depending on the angle, start moving
         animation["attackrun"].weight = animation["attackrun"].speed = move;
         direction = transform.TransformDirection(Vector3.forward);// * attackSpeed * move);
         characterController.SimpleMove(direction * attackSpeed * move);
         
         yield;
     }
     
     // Run towards player
     var timer = 0.0;
     var lostSight = false;
     while (timer < extraRunTime)
     {
         angle = RotateTowardsPosition(target.position, attackRotateSpeed);
             
         // The angle of our forward direction and the player position is larger than 50 degrees
         // That means he is out of sight
         if (Mathf.Abs(angle) > 40)
             lostSight = true;
             
         // If we lost sight then we keep running for some more time (extraRunTime). 
         // then stop attacking 
         if (lostSight)
             timer += Time.deltaTime;    
         
         // Just move forward at constant speed
         direction = transform.TransformDirection(Vector3.forward * attackSpeed);
         characterController.SimpleMove(direction);
 
         // Keep looking if we are hitting our target
         // If we are, knock them out of the way dealing damage
         var pos = transform.TransformPoint(punchPosition);
         if(Time.time > lastPunchTime + 0.3 && (pos - target.position).magnitude < punchRadius)
         {//3 
             // deal damage
             target.SendMessage("ApplyDamage", damage);
             // knock the player back and to the side
             var slamDirection = transform.InverseTransformDirection(target.position - transform.position);
             slamDirection.y = 0;
             slamDirection.z = 1;
             if (slamDirection.x >= 0)
                 slamDirection.x = 1;
             else
                 slamDirection.x = -1;
             target.SendMessage("Slam", transform.TransformDirection(slamDirection));
             lastPunchTime = Time.time;
         }
 
         // We are not actually moving forward.
         // This probably means we ran into a wall or something. Stop attacking the player.
         if (characterController.velocity.magnitude < attackSpeed * 0.3)
             break;
         
         // yield for one frame
         yield;
     }
 
     isAttacking = false;
     
     // Now we can go back to playing the idle animation
     animation.CrossFade("idle");
 }