Object does not follow path correctly

I am trying to have an object follow a path which basically is a square: the object moves to the next corner and pauses for some time. The movement is correct initially, however, after sometime it goes crazy and I have no clue why. The following shows what I am talking about:

1. Correct movement phase.

2. Beginning of deviations phase: the object is not following the square edges correctly.

3. Crazy movements phase.

The function that does this is Patrol() in the following code:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

namespace Game
{
    public class PatrollingEnemyBehaviour : EnemyBehaviour
    {
        public Vector3[] path;
        protected override void Update()
        {         
            base.Update();
            StartCoroutine(Patrol());            
        }

        private IEnumerator Patrol()
        {                      
            while (true)
            {
                if (m_TargetToShoot || m_Target)
                {
                    yield break;
                }
                foreach (Vector3 position in path)
                {
                    if (m_TargetToShoot || m_Target)
                    {
                        yield break;
                    }
                    Debug.Log("Going to: " + position);                    
                    m_NavMeshAgent.SetDestination(position);
                    yield return new WaitForSeconds(5);                    
                }   
            }            
        }
    }
}

The path is set within Unity editor to be the square.

The update function from the parent class deals with player detection and taking action.

Cheers.