Why does collision only work when keys are being pressed?

Question

My player object containing a rigidbody that is controlled using Input, is not colliding with an enemy unless keys are pressed. When no keys are pressed, the enemy simply goes through the player without collision. I'm using Unity 5.6.1f1.

I figured the problem is in the Patrol class because when I don't attach the script to the enemy object the collision appears to take place fine. But I don't know what I'm doing wrong in this script because I seems to do it's task well. I wrote this script to make the enemy object move between points in patrolPoints which are just some empty's in the game world.

So, I would like to know if I'm doing it right or is there another way to do it.

Patrol.cs

public class Patrol : MonoBehaviour {
    public Transform[] patrolPoints;
    public float speed;
    private int currentPoint;
    private bool forward;

    // Use this for initialization
    void Start () {
        transform.position = patrolPoints [0].position;
        currentPoint = 0;
        forward = true;
    }

    // Update is called once per frame
    void Update () {
        if (transform.position == patrolPoints [currentPoint].position) {
            if (currentPoint < patrolPoints.Length - 1 && forward) {
                currentPoint++;
            } else {
                currentPoint--;
                forward = false;
            }

            if (currentPoint == 0)
                forward = true;
        }   

        transform.position = Vector3.MoveTowards (transform.position, 
            patrolPoints [currentPoint].position, speed * Time.deltaTime);
    }
}

Answer 1

Move your bodies around using Rigidbody.AddForce, by modifying Rigidbody.velocity vector, or using Rigidbody.MovePosition. These should ensure that collisions continue to work, whereas your line

transform.position = Vector3.MoveTowards (transform.position, patrolPoints [currentPoint].position, speed * Time.deltaTime);

will break collision functionality.