OverlapSphere only works on a semi-sphere

Hi,
I'm trying to add a Field of View for my AI like in this tutorial:

. The problem I'm getting is that it seems that the OverlapSphere only works on the half of the sphere it is supposed to. Also the Gizmo I use with the same parameters shows a Sphere properly, so I have no clue what the error is.

(In the image below, Up equals to the Z axis and right to the X axis)

The code is the following:
private void FieldOfViewCheck()
{
Collider[] rangeChecks = Physics.OverlapSphere(transform.position, inner_radius+external_radios_offSet);
List<Agent> enemigos = new List<Agent>();
foreach (Collider ene in rangeChecks)
{
Agent enemy = ene.GetComponent<Agent>();
if(enemy!=null){
if (enemy==this.GetComponent<Agent>()) //Checking the agent is not itself
break;
if ( equipo!=null && enemy.equipo!=null){ //Checking they are from different teams

if(equipo.id==enemy.equipo.id){
break;
}

}

Transform target = enemy.transform;
Vector3 directionToTarget = (target.position - transform.position).normalized;

//Debug.Log(Vector3.Angle( angleVectorFromFront(0), directionToTarget));
//This would show properly the angle between the agent and the enemy. And it stops if you
// leave the red are of the picture. So I'm pretty sure the problem is with the SphereCollider


if (Vector3.Angle( angleVectorFromFront(0), directionToTarget) < (close_angle+broad_angle_offSet) / 2)
{ //angleVectorFromFront(0) works as transform.forward
float distancia = Vector3.Distance(transform.position, target.position);

if (!Physics.Raycast(transform.position, directionToTarget, distancia, mascaraObstaculos)){
//Checking there is not an obstacle in between
enemigos.Add(enemy);
enemigo = enemy;
}
}
}
}
if(enemigos.Any())
actualizaEnemigo(enemigos);
}


I hope you can help me, thank you for your time