PHP jQuery DATA-VALUE

$(document).ready(function() {
  $("body").on("click", "a", function(event) {
            
    event.preventDefault();

    var classenlace = "." + $(this,"a").prop("class");
    //var section = $(this).prop("id");
    var section = this.id;
    
    $.ajax({
      url: $(this).prop("href")                 
    })                                                     .done(function(data) {
      if (data) {
        if(section == "enlace" ) {
          var name = $(classenlace).data('name');
          var lastname =    $(classenlace).data('lastname');
        }
       }
    });
  });
});

<?php
  foreach ($conection->query($result3) as $row3) {
    $name = $row3['name'];
    $lastname =row3['lastname'];
?>

<a href="ficha.php" id="enlace" class="enlace"
data-name = "<?php echo $name; ?>"
data-lastname = "<?php echo $lastname; ?>">
  <?php echo  "- ".$name." ".$lastname; ?>
</a>

<?php
  }
?>

To forgive my English

This code is not working,

There are 5 names and surnames:

John smith
Juan Garcia
Michel Van
Bob Dereck Michael Jackson

Any of the 5 links always returns: John smith

Why is this happening?

</div>

You must use the attr element of jQuery, it is better, try with the following code, first extract the data-name and data-lastname values and then send them as parameters inside the ajax function next to the url

$(document).ready(function() {
   $("body").on("click", "a", function(event) {         
    event.preventDefault(); 
    if($(this).attr("id").valueOf() == "enlace"){
        var name = $(this).attr("data-name").valueOf();
        var lastname =  $(this).attr("data-lastname").valueOf();
    }
    alert(name + " " + lastname);
    $.ajax({
     url: $(this).attr("href").valueOf() 
     
    }).done(function(data) {
     
    });
  });
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<a href="ficha.php?" id="enlace" class="enlace"
data-name = "name1"
data-lastname = "lastname1">
  Name1
</a>
<a href="ficha.php?" id="enlace" class="enlace"
data-name = "name2"
data-lastname = "lastname2">
  Name2
</a>
<a href="ficha.php?" id="enlace" class="enlace"
data-name = "name3"
data-lastname = "lastname3">
  Name3
</a>

</div>

You should use $(this) instead of $(this,"a") in the JavaScript part.