Trouble in following path of line renderer...

Hi, I have written code of drawing line using line renderer by mouse drag, path is drawn, and then i want to follow mycube as per it with smoothly, my cube can follow for the first drag, if i draw, one more time, then it is not able to follow smoothly, for that i have written below code , please suggest me what i am doing wrong?

 using UnityEngine;
 using System.Collections;
 using System.Collections.Generic;
 using Vectrosity;
 
 public class DrawLine : MonoBehaviour 
 {
     VectorLine myLine1;
     VectorLine recentLine;
     public Material lineMat;
 
 
     private float startTime;
     private float journeyLength;
     public float speed = 1.0F;
     public Vector3 lastPos;
     Vector3[] myRoute;
 
     private LineRenderer line;
     private bool isMousePressed;
     private List<Vector3> pointsList;
     private Vector3 mousePos;
     private bool startLineAnimation;
     // Structure for line points
     struct myLine
     {
         public Vector3 StartPoint;
         public Vector3 EndPoint;
     };
     //    -----------------------------------    
     void Awake()
     {
         line = gameObject.GetComponent<LineRenderer> ();
         line.SetVertexCount(0);
         line.material = lineMat;
         line.renderer.enabled = true;;
         line.useWorldSpace = true;    
         isMousePressed = false;
         startLineAnimation = false;
         pointsList = new List<Vector3>();
     }
 
 
     //    -----------------------------------    
     void Update () 
     {
         // If mouse button down, remove old line and set its color to green
         if(Input.GetMouseButtonDown(0))
         { 
             Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
             RaycastHit hit;
             if (Physics.Raycast(ray, out hit, 100))
             {
                 if (hit.transform.gameObject == transform.gameObject)
                 {
                 isMousePressed = true;
                 line.SetVertexCount(0);
                 pointsList.RemoveRange(0,pointsList.Count);
                 }
             }
             //line.SetColors(Color.green, Color.green);
         }
         else if(Input.GetMouseButtonUp(0))
         {
             if(isMousePressed)
             {
             isMousePressed = false;
             DrawMe();
             }
         }
         // Drawing line when mouse is moving(presses)
         if(isMousePressed)
         {
             mousePos = Camera.main.ScreenToWorldPoint(Input.mousePosition);
             mousePos.z=0;
             if (!pointsList.Contains (mousePos)) 
             {
                 pointsList.Add (mousePos);
                 line.SetVertexCount (pointsList.Count);
                 line.SetPosition (pointsList.Count-1 , (Vector3)pointsList [pointsList.Count-1]);
 
 //                StartCoroutine(add (mousePos));
 //                if(isLineCollide())
 //                {
 //                    isMousePressed = false;
 //                    //line.SetColors(Color.red, Color.red);
 //                }
             }
         }
         if (startLineAnimation && recentLine.active) {
 
                         recentLine.textureOffset = -Time.time * 2.0f % 1f;
 
                         StartCoroutine(StartFollowing());
 
                 }
 
     }
 
     IEnumerator StartFollowing () {
                 
                 int  counter = 0;
                 Vector3 pointA = transform.position;
                 Vector3 pointB = myRoute[counter];
                 print ("pointA:"+pointA);
                 print ("pointB:"+pointB);
                 while (counter<=myRoute.Length-1) {
                         yield return StartCoroutine(MoveObject(transform, pointA, pointB, 3.0f));
                         counter++;
                         if(counter<=myRoute.Length-1)
                             {
                             pointA=pointB;
                             pointB = myRoute[counter];
                             }
 
                         //yield return StartCoroutine(MoveObject(transform, pointB, pointA, 3.0f));
                     }
             }
 
     IEnumerator MoveObject (Transform thisTransform, Vector3 startPos, Vector3 endPos, float time) {
                 var i= 0.0f;
                 var rate= 2.0f/time;
                 while (i < 1.0f) {
                     i += Time.deltaTime * rate;
                     thisTransform.position = Vector3.Lerp(startPos, endPos, i);
                     yield return null; 
                 }
             }
 
 
     public void DrawMe()
     {
         line.enabled = false;
 
          myRoute = new Vector3[pointsList.Count];
         int i ;
         for (i=0; i<pointsList.Count; i++) 
         {
 
             myRoute[i] = pointsList[i];
             print(i+" : "+myRoute[i]);    
         
         }
     
          lastPos = myRoute[i-1];
         print (lastPos);
         VectorLine.Destroy(ref myLine1);
 
         myLine1 = new VectorLine ("Line1", myRoute, lineMat, 2.5f, LineType.Continuous);
         myLine1.textureScale = 5.0f;
         recentLine = myLine1;
         myLine1.Draw ();
 
         startLineAnimation = true;
 
         //for (int i=0; i<myRoute.Length; i++) 
         //{
         startTime = Time.time;
         journeyLength = Vector3.Distance(transform.position, lastPos);    
 
             
         //}
 
         /*myLine1 = VectorLine.SetLine (Color.cyan, myRoute);
         myLine1.smoothWidth = true;
         myLine1.material = lineMat;*/
     }
 
 }