How enemy AI follows player without diagonal movement? (2D)

Hello,

I'm trying to make a game like pac-man and i want my enemy to follow my player if my player goes into its range. I used way points to move my enemies and want them to follow my player until my player leaves the range. After that it should go back to patrolling. However, in my game if the player and enemies are at the same horizontal line(same y axis), enemy moves unit by unit (very slowly). If the player and enemies are at the same vertical line (same x axis), enemy waits until my character stops then rushes into the character.

I need my enemy to move vertically or horizontally according to my player.

  void FixedUpdate() {
         Vector3 direction = player.position - transform.position;
         if (transform.position != waypoints[cur].position) {
             if (Distance() < 4f) {
                 if (Mathf.Abs(direction.x) < Mathf.Abs(direction.y) && Mathf.Abs(direction.x) > Mathf.Epsilon) {
                     direction.y = 0;
                 }
                 else if(Mathf.Abs(direction.y) < Mathf.Abs(direction.x) && Mathf.Abs(direction.y) > Mathf.Epsilon) {
                     direction.x = 0;
                 }
                 transform.position = Vector2.MoveTowards(transform.position, transform.position + direction, speed * Time.deltaTime);
             }
             else {
                 Vector2 movePoint = transform.position = Vector2.MoveTowards(transform.position, waypoints[cur].position, speed * Time.deltaTime);
 
                 GetComponent<Rigidbody2D>().MovePosition(movePoint);
             }
            
         }
         else {
             cur = (cur + 1) % waypoints.Length;
         }
     }