Collider2D[] results = new Collider2D[16];
int count = rb2d.OverlapCollider(contactFilter, results);
for (int i = 0; i < count; i++)
{
    Collider2D result = results[i];
    Tilemap breakableMap = result.gameObject.GetComponent<Tilemap>();
    breakableMap.SetTile(breakableMap.WorldToCell(..........), null);
}