✅ Case1 Failed: LeetCode Binary Tree Level Order Traversal

public class Solution {
    public IList<IList<int>> LevelOrder(TreeNode root) {
        List<IList<int>> res = new();
        List<int> separation = new();
        if(root == null){
            return res;
        }
        Queue<TreeNode> q = new Queue<TreeNode>();
        q.Enqueue(root);
        int levelCount = 1;
        while(q.Count > 0){
            TreeNode visited = q.Dequeue();
            
                if(visited.left != null){
                    q.Enqueue(visited.right);

                }

                if(visited.right != null){

                    q.Enqueue(visited.left);
                }
                separation.Add(visited.val);
                levelCount--;
                if(levelCount == 0){
                    res.Add(separation);
                    levelCount = q.Count;
                    
                }
        }
        return res;


    }
}