Obstacle Holders don't keep spawning

Hey everyone, so I'm creating a 2D Endless Runner. I have my Spawner script as well as Spawner points that i placed in the scene. My obstacles spawn and move on the X axis, to the left.

I have my array of obstacles and i drag my obstacle prefabs into the element slots in the inspector. This script works great for spawning individual obstacles. But if i add an Obstacle Holder prefab that i created that only has around 10 obstacles in each holder, it spawns the Holder and then it stops spawning everything all together. It won't even spawn the individual obstacles. I of course need the obstacles to keep spawning, but it stops for some reason after the Holder spawns.

Any idea why it doesn't keep spawning the obstacles? Do i need to change something in the code? Heres my code Im using. I am new to coding, and Unity, so i appreciate any help.

Code (CSharp):

1. public class Spawner : MonoBehaviour
2. {
3.     [SerializeField] float minSpawnTime, maxSpawnTime;
4.  
5.     [SerializeField] GameObject[ ] obstacles;
6.     [SerializeField] Transform obstaclesPos;
7.  
8.     Transform[ ] lastPoss;
9.     float[ ] lastSpeed;
10.  
11.     private void Awake()
12.     {
13.         lastPoss = new Transform[obstaclesPos.childCount];
14.         lastSpeed = new float[obstaclesPos.childCount];
15.  
16.         for (int i = 0; i < lastSpeed.Length; i++)
17.         {
18.             lastSpeed[i] = -1;
19.         }
20.     }
21.  
22.     void Start()
23.     {
24.         // StartObstaclesMove();
25.     }
26.  
27.     public void StartObstaclesMove()
28.     {
29.         StartCoroutine(InstanteObstacels(0f));
30.     }
31.  
32.     IEnumerator InstanteObstacels(float dt)
33.     {
34.         float waitTime = 1f;
35.         yield return new WaitForSeconds(waitTime);
36.  
37.         if (GameManager.instance.bGameStarted)
38.         {
39.             int rr = Random.Range(0, obstaclesPos.childCount);
40.  
41.             Transform tt = obstaclesPos.GetChild(rr);
42.             int randomObstacle = Random.Range(0, obstacles.Length);
43.  
44.             GameObject obs = GameObject.Instantiate(obstacles[randomObstacle]);
45.             obs.transform.position = tt.position;
46.  
47.             waitTime = Random.Range(minSpawnTime, maxSpawnTime);
48. 
            yield return new WaitForSeconds(waitTime);
49.  
50.  
51.     if (canGo(rr, obs.transform.position.x, obs.GetComponent<ObstacleMovement>().moveSpeed))
52.             {
53.                 lastPoss[rr] = obs.transform;
54.                 lastSpeed[rr] = obs.GetComponent<ObstacleMovement>().moveSpeed;
55.             }
56.             else
57.             {
58.                 Destroy(obs);
59.             }
60.  
61.             StartCoroutine(InstanteObstacels(dt));
62.         }
63.     }
64.  
65.     bool canGo(int rr, float x1, float s1)
66.     {
67.  
68.         if (lastPoss[rr] == null || lastSpeed[rr] < 0) return true;
69.  
70.         float x = lastPoss[rr].position.x;
71.         float s = lastSpeed[rr];
72.  
73.         float t1, t2;
74.  
75.         t1 = (x + 10) / s;
76.         t2 = (x1 + 10) / s1;
77.  
78.         if (t2 > t1) return true;
79.  
80.         return false;
81.     }
82. }