Argument out of range

In my really simple simon says game, everything used to be working fine. The game would generate a pattern, and when the player got the pattern correct, the computer would give the same thing but add another color. However, when I went to add a high score system, basically everything broke. On the second round of a pattern, the first color would not repeat, and I get an error that says 'Argument out of range'. Its probably something really easy to fix, I don't see anything wrong with it, but if anyone else does, I would really appreciate it. My script:

 using UnityEngine;
 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine.UI;
 
 public class GameManager : MonoBehaviour {
 
     public SpriteRenderer[] colors;
 
     public AudioSource[] buttonSounds;
 
     private int colorSelect;
 
     public float lit;
 
     private float litCounter;
 
     public float waitBetweenLight;
 
     private float waitBetweenCounter;
 
     private bool shouldBeLit;
 
     private bool shouldBeDim;
 
     public List <int> activeSequence;
 
     private int posInSequence;
 
     private bool gameActive;
 
     private int inputInSequence;
 
     public AudioSource correct;
 
     public AudioSource incorrect;
 
     public Text scoreText;
 
     // Use this for initialization
     void Start () {
 
         if (!PlayerPrefs.HasKey ("High Score")) {
             PlayerPrefs.SetInt ("High Score", 0);
         }
 
         scoreText.text = "Score: 0 - High Score: " + PlayerPrefs.GetInt("High Score");
 
     }
     
     // Update is called once per frame
     void Update () {
 
         if (shouldBeLit) {
             litCounter -= Time.deltaTime;
             if (litCounter < 0) {
                 colors [activeSequence[posInSequence]].color = new Color (colors [activeSequence[posInSequence]].color.r, colors [activeSequence[posInSequence]].color.g, colors [activeSequence[posInSequence]].color.b, 0.5f);
                 buttonSounds [activeSequence [posInSequence]].Stop();
                 shouldBeLit = false;
 
                 shouldBeDim = true;
                 waitBetweenCounter = waitBetweenLight;
 
                 posInSequence++;
             }
         }
         if (shouldBeDim) {
             waitBetweenCounter -= Time.deltaTime;
 
             if (posInSequence >= activeSequence.Count) {
 
                 shouldBeDim = false;
                 gameActive = true;
 
             } else {
                 if (waitBetweenCounter > 0) {
                     
                     /*colorSelect = Random.Range (0, colors.Length);
 
                     activeSequence.Add (colorSelect);*/
 
                     colors [activeSequence[posInSequence]].color = new Color (colors [activeSequence[posInSequence]].color.r, colors [activeSequence[posInSequence]].color.g, colors [activeSequence[posInSequence]].color.b, 1f);
 
                     buttonSounds [activeSequence [posInSequence]].Play();
 
                     litCounter = lit;
                     shouldBeLit = true;
                     shouldBeDim = false;
                 }
             }
         }
     }
 
     public void StartGame () {
 
         activeSequence.Clear ();
 
         posInSequence = 0;
 
         colorSelect = Random.Range (0, colors.Length);
 
         activeSequence.Add (colorSelect);
 
         colors [activeSequence[posInSequence]].color = new Color (colors [activeSequence[posInSequence]].color.r, colors [activeSequence[posInSequence]].color.g, colors [activeSequence[posInSequence]].color.b, 1f);
 
         buttonSounds [activeSequence [posInSequence]].Play();
 
         litCounter = lit;
         shouldBeLit = true;
 
         scoreText.text = "Score: 0 - High Score: " + PlayerPrefs.GetInt("High Score");
     }
 
     public void ColourPressed(int whichButton){
 
         if (gameActive) {
 
 
 
             if (activeSequence[inputInSequence] == whichButton) {
                 Debug.Log ("Correct");
 
                 inputInSequence++;
 
                 if (inputInSequence >= activeSequence.Count) {
 
                     PlayerPrefs.SetInt ("High Score", activeSequence.Count);
                 }
 
                     if (activeSequence.Count > PlayerPrefs.GetInt("High Score")){
 
                     scoreText.text = "Score: " + activeSequence.Count + "High Score" + PlayerPrefs.GetInt("High Score");
 
                     posInSequence = 0;
 
                     inputInSequence = 0;
 
                     colorSelect = Random.Range (0, colors.Length);
 
                     activeSequence.Add (colorSelect);
 
                     colors [activeSequence[posInSequence]].color = new Color (colors [activeSequence[posInSequence]].color.r, colors [activeSequence[posInSequence]].color.g, colors [activeSequence[posInSequence]].color.b, 1f);
 
                     buttonSounds [activeSequence [posInSequence]].Play(); 
 
                     litCounter = lit;
                     shouldBeLit = true;
 
                     gameActive = false;
 
                     correct.Play ();
 
                 }
 
             } else {
                 Debug.Log ("Wrong");
                 incorrect.Play ();
                 gameActive = false;
             }
         }
 
     }
 }

Edit: So I re-typed the code , and I'm not sure what was wrong, but it fixed itself.