Increment doesnt increment after the first increment

I am just trying to use a simple increment to indicate what level to load next after a collision. My levels are named as level 1, level 2 and so on. When I run the game, the initial increment works fine and goes to 2 thus loading my level 2 when I collide. After that, the increment always stays at 2 and doesn't increment to 3,4 and so on. Please advice what I am doing wrong. Thank you.

 public int level;
 
     void Start()
     {
         level = 1;
     }
 
     void OnCollisionEnter(Collision collision)
     {
         if (collision.gameObject.tag == "Player")
         {
             if (level < 10)
             {
                 level++;
                 Application.LoadLevel("level_" + level);
                 Debug.Log(level);
             }         
         }
     }