How to display information form a database about gender user? - php

Question

In the database I have a gender table where male is M and female is F. Then I want to display full information about the gender of the user, so if M is to be male, and if F is to be female. The problem is that it always displays Female. Can someone see the code and give a hint where the error lies?
public function getData()
{
$id = $_GET['id'];
$sql = $this->database->connect()->prepare("SELECT user.id, first_name, last_name, avatar, birth_date, gender, age, school, work, city, martial_status, number_phone FROM user JOIN user_data ON user.id = user_data.user_id where user.id = :abc and user_id = :abc");
$sql->bindParam(':abc',$id, PDO::PARAM_INT);
$sql->execute();
if($sql->rowcount())
{
$row = $sql->fetch();
}
$this->userData = $row;
}
public function display(string $colName)
{
echo (isset($this->userData[$colName])) ? $this->userData[$colName] : '';
}
<main>
<div class='container'>
<div class="row">
<div class="col-xl-12 d-flex justify-content-center">
<div id="name"><span><?php echo $profil->display('first_name') ?></span> <span><?php echo $profil->display('last_name') ?></span></div>
</div>
</div>
<div class="row" id="margin">
<div class="col-xl-12 d-flex justify-content-center">
<div>Płeć: <?php if($profil->display('gender')=='M'){ echo "Mężczyzna";} else{ echo "Kobieta";} ?></div>
</div>
</div>
</div>
</main>