Variable changing randomly

Hello, my script wont work. I've started working on a door script to make adding doors easier. But the script just wont work, and I cant figure out why.

 //Door
 public GameObject door;

 //The position of the door when open
 public GameObject openDoor;

 //Distance that the door opens
 public float openDistance;

 //The speed the door opens
 public float openSpeed;

 //The speed the door closes
 public float closeSpeed;

 //Player tag
 public string playerTag;

 //The player found by tag
 GameObject player;

 //Where the door starts
 Transform startPos;

 void Start()
 {
     //Finds the player with said tag
     player = GameObject.FindGameObjectWithTag(playerTag);

     //Sets the start position of the door
     startPos = door.transform;
 }

 // Update is called once per frame
 void Update()
 {
     //Calculate the distance
     float distance = Vector3.Distance(player.transform.position, transform.position);

     //Open door
     if (distance <= openDistance)
     {
         //Calculate the movement
         float xPos = Mathf.Lerp(door.transform.position.x, openDoor.transform.position.x, openSpeed);
         float yPos = Mathf.Lerp(door.transform.position.y, openDoor.transform.position.y, openSpeed);
         float zPos = Mathf.Lerp(door.transform.position.z, openDoor.transform.position.z, openSpeed);

         //Set the position of the door
         door.transform.position = new Vector3(xPos, yPos, zPos);

         //Calculate the rotation
         float xRot = Mathf.Lerp(door.transform.rotation.x, openDoor.transform.rotation.x, openSpeed);
         float yRot = Mathf.Lerp(door.transform.rotation.y, openDoor.transform.rotation.y, openSpeed);
         float zRot = Mathf.Lerp(door.transform.rotation.z, openDoor.transform.rotation.z, openSpeed);

         //Set the rotation of the door
         door.transform.rotation = new Quaternion(xRot, yRot, zRot, door.transform.rotation.w);
     }

     //Close door
     if (distance >= openDistance)
     {
         //Calculate the movement
         float xPos = Mathf.Lerp(door.transform.position.x, startPos.position.x, closeSpeed);
         float yPos = Mathf.Lerp(door.transform.position.y, startPos.position.y, closeSpeed);
         float zPos = Mathf.Lerp(door.transform.position.z, startPos.position.z, closeSpeed);

         //Set the position of the door
         door.transform.position = new Vector3(xPos, yPos, zPos);

         //Calculate the rotation
         float xRot = Mathf.Lerp(door.transform.rotation.x, startPos.rotation.x, closeSpeed);
         float yRot = Mathf.Lerp(door.transform.rotation.y, startPos.rotation.y, closeSpeed);
         float zRot = Mathf.Lerp(door.transform.rotation.z, startPos.rotation.z, closeSpeed);

         //Set the rotation of the door
         door.transform.rotation = new Quaternion(xRot, yRot, zRot, door.transform.rotation.w);
     }
 }

Thank you in advance, I'm sure I just missed something stupid...

EDIT,

The startPos variable is changing and I cant figure out why. The door moves, But won't move back. I have an empty game object that just holds all the components; the door object the script and the open door game object. The script was working perfectly, I exited out of unity and came back later and it wouldn't work.