Player not taking Health Damage

I have a player health game ( player is yellow) I am starting - a cube trying to pass three obstacles

I have fooled around with the rigid body on the player and also freezing the rotation when it hits a object

at times the players hits the last two obstacles - or at times has gone right through them, The last obstacles either goes right through the player or hits it and does not do damage at all?

Thank you

Code (CSharp):

1. using UnityEngine;
2.  
3. public class plankRotate : MonoBehaviour {
4.     public float Speed = 50f;
5.     public float Damage = 10f;
6.  
7.     void Start () { }
8.  
9.     void Update ()
10.     {
11.         transform.Rotate(Vector3.up * Time.deltaTime * Speed);
12.     }
13.  
14.     void OnCollisionEnter (Collision other)
15.     {
16.         var health = other.gameObject.GetComponent<HealthScript>();
17.         if (health != null)
18.             health.TakeDamage(Damage);
19.     }
20. }

Code (CSharp):

1. using UnityEngine;
2.  
3. public class HealthScript : MonoBehaviour {
4.     public GameManager Manager;
5.     public GameObject HealthBarCanvas;
6.     public playermove Movement;
7.     public MeshRenderer MeshRenderer;
8.     public RectTransform BarTransform;
9.     public float max_health = 600f;
10.     public float cur_health;
11.     public bool alive = true;
12.  
13.     float minDelta = .01f;    //SizeDelta "Off" where bar is empty
14.     float maxDelta = 1.8f; //SizeDelta "On" where bar is full
15.  
16.     void Start () {
17.         Reset();
18.     }
19.  
20.     public void TakeDamage(float amount) {
21.         if (!alive) return;
22.  
23.         cur_health -= amount;
24.         SetHealthBar();
25.  
26.         if (cur_health  <= 0)
27.             Die();
28.     }
29.  
30.     public void SetHealthBar () {
31.         float barRatio = minDelta + (maxDelta - minDelta) * Mathf.Clamp(cur_health / max_health, 0f, 1f);
32.         BarTransform.sizeDelta = new Vector2(barRatio, BarTransform.sizeDelta.y);
33.     }
34.  
35.     public void Reset() {
36.         cur_health = max_health;
37.         alive = true;
38.  
39.         HealthBarCanvas.SetActive(true);
40.         SetHealthBar();
41.  
42.         Movement.enabled = true;
43.         MeshRenderer.enabled = true;
44.     }
45.  
46.     public void Die() {
47.         cur_health = 0;
48.         alive = false;
49.  
50.         //Stop the player from moving.
51.         Movement.enabled = false;
52.  
53.         //Make the player disappear
54.         MeshRenderer.enabled = false;
55.  
56.         //Disable the health bar
57.         HealthBarCanvas.SetActive(false);
58.  
59.         //Tell the GameManager we died
60.         Manager.OnDeath();
61.     }
62. }
63.