noobNeedsHelp with writing script for movement

Hi all, visually here is what i'm trying to do:

1: From the ' X ' my Object moves horizontally to the wall on the left. It collides with the wall that I've tagged 'SheetEnd'.

1. I want to have the object (the dark blue piece) reset its transform.position back to X, where it repeats motion #1. I can do this, but having it continue the movement will not work if I use time.Time.

I'll add the code...I feel i'm close...and am over-complicating this....any hints... or right directions would help.

   void Start()
 {
     initialPosition = transform.position;
 }

 // Update is called once per frame
 void Update()
 {
     //make a method that moves the MusicGuide from left to right
     if (state == State.Moving)
     {
         ScanLeftRight();
     } 
     if (state == State.FinishedMoving)
     {
         print("DING!");
         // Reset position and timer (if that's possible)
         // Change state back to Moving. 
     }
 }

 public void ScanLeftRight()
 {

     float timer = 0f;
     timer += Time.time;
     Vector3 musicGuidePosition = initialPosition + (vectorMagnitude * multiplier * (timer)); 
     transform.position = musicGuidePosition;

     // Ignore this code, was playing around with Sin() //
     //take an initial transform position and add an offset with respect to time. 
     //float cycle = Time.time / period;
     //float tau = 2 * Mathf.PI;
     //float oscillatingVector = Mathf.Sin(cycle * tau) / 2 + 0.5f;
     //print(oscillatingVector);
     //Vector3 musicGuidePosition = initialPosition - (vectorMagnitude * oscillatingVector);
     // update object's position so that it will move when game is running.
     //transform.position = musicGuidePosition;


 }

 private void ResetPosition()
 {
     if (state == State.FinishedMoving)

     {
         transform.position = new Vector3(8f, 10f, 4f);
         print("Reset Position " + transform.position);
                    
     }
 }

 void OnTriggerEnter(Collider other)
 {
     if (other.tag == "SheetEnd") // I have used the same tag that you attached to your enemy character
     {
         Debug.Log("Code made it this far... tagged ->");
         state = State.FinishedMoving;
         
         //reset position back to initial starting point once it reaches set distance
         ResetPosition();

     }
 } }