Unity Event System only activates around 60 times

I'm currently working on an N-Body Simulation to try out some new things, one of which being the event system in Unity. The problem I'm facing is, although it once worked ( I believe perfectly ), it now only activates around 60 times. What I'm doing is spawning a given amount of Planets in a loop, each time this happens an Event is triggered which sends the current planet's GameObject to a different script which adds it to a List so that it knows on which GameObjects it needs to do calculations. Here are the two important snippets of code:

    public class PlanetSpawnHandler : MonoBehaviour
{
    public int startPlanetCount;
    public float spawnRadius;
    public GameObject planetPrefab;
    public float startForce;

    GameObject[] sunArray;
    //Event and EventArgs
    public event EventHandler<OnPlanetSpawnedArgs> OnPlanetSpawned;
    public class OnPlanetSpawnedArgs : EventArgs
    {
        public GameObject planetArg;
    }

    //Start is called before the first frame update
    void Start()
    {
        
        sunArray = GameObject.FindGameObjectsWithTag("Sun");

        foreach (GameObject sun in sunArray)
        {
            OnPlanetSpawned?.Invoke(this, new OnPlanetSpawnedArgs { planetArg = sun });
        }
        for (int o = 0; o < sunArray.Length; o++)
        {
            float x = sunArray[o].transform.position.x;
            float y = sunArray[o].transform.position.y;
            float z = sunArray[o].transform.position.z;
            for (int i = 0; i < startPlanetCount; i++)
            {
                //Calculations for Planet Spawning
                Vector3 instantiatePos = new Vector3(x - UnityEngine.Random.Range(-spawnRadius, spawnRadius), y - UnityEngine.Random.Range(-spawnRadius, spawnRadius), z - UnityEngine.Random.Range(-spawnRadius, spawnRadius));
                GameObject planet = Instantiate(planetPrefab, instantiatePos, Quaternion.identity);
                Rigidbody rb = planet.GetComponent<Rigidbody>();
                rb.AddForce(startForce * rb.mass, startForce * rb.mass, startForce * rb.mass);
                
                //Triggering the Event
                OnPlanetSpawned?.Invoke(this, new OnPlanetSpawnedArgs { planetArg = planet });
                //Debug.Log("Spawned Planet");
            }
        }
    }

And the listener:

public class Attraction: MonoBehaviour
{
    List<GameObject> planetList = new List<GameObject>();
    private void OnEnable()
{
    //Subscribing to Event
    PlanetSpawnHandler planetSpawnHandler = GetComponent<PlanetSpawnHandler>();
    planetSpawnHandler.OnPlanetSpawned += AddPlanetToList;

    
    //Debug.Log(planetSpawnHandler);
}

// Update is called once per frame
private void FixedUpdate()
{
    //Shitty code, pls ignore
    foreach (GameObject planet in planetList)
    {
        if (planet == null)
            continue;
        else
        {
            foreach (GameObject otherPlanet in planetList)
            {

                if (planet == otherPlanet)
                    continue;
                else
                {
                    if (otherPlanet == null)
                        continue;
                    else
                    {
                        Rigidbody planetRb = planet.GetComponent<Rigidbody>();
                        Rigidbody otherPlanetRb = otherPlanet.GetComponent<Rigidbody>();

                        Vector3 direction = planetRb.position - otherPlanetRb.position;
                        float distance = direction.magnitude;
                        float forceMagnitude = (planetRb.mass * otherPlanetRb.mass) / Mathf.Pow(distance, 2) * 1000f;
                        Vector3 force = direction.normalized * forceMagnitude;

                        otherPlanetRb.AddForce(force);
                    }



                }
            }
        }
    }
    
}
//Function for Event
public void AddPlanetToList(object sender, PlanetSpawnHandler.OnPlanetSpawnedArgs planet )
{
    Debug.Log("AddPlanet called");
    planetList.Add(planet.planetArg);
    Debug.Log(planetList.Count + " In List");
}

As I said, the problem is that the listener only receives 60 messages from the Publisher, although I'm sure it once worked perfectly.

If you need any other information, tell me and I will provide it