Collision doesn't trigger action only for that object

Unity Engine
1

I’m trying to get the collision to cause the game to be over. I didn’t put it at the scripting section because it works fine with other objects besides the “obstacle”. I ticked the obstacle as ‘is trigger’ and also the ‘head’. However, it still doesn’t works. I might post a picture if this is too vague.

Thanks for helping!

    void OnTriggerEnter(Collider coll) {
        // Food?
        if (coll.name.StartsWith ("Coin")) {
            // Get longer in next Move call
            ate = true;
           
            // Remove the Food
            Destroy (coll.gameObject);
        }
        // Collided with Tail or Border
        if (coll.name.StartsWith ("Obstacle")) {

            Destroy (head);
            // ToDo 'You lose' screen
        }
    }
2

Why do not you use tags?