How to retain the form inputs when submit button is clicked? - php

Question

So I got a form that gets the student basic information for temporary admission, so I have a function that when register/submit button is clicked it checks if the Or number is already exist in database when it does it displays error message and the inputted data stays in their own fields.
the function works but when a user inputted a name for example "james joseph" and or number exist in database it will retain the name "james" only.
is there a way that it retains both?
Here's my code for the form
<form class="form-group" method="post" action="index.php">
<div class="row"><!--Top row-->
<div class="col-lg-5"><p><h3>Register an Enrollee</h3></p></div>
<div class="col-lg-3"></div>
<div class="col-lg-4">
</div>
</div>
<br>
<br>
<div class="row">
<div class="col-lg-4">
<label>Academic Year </label>
<?php
if (isset($_GET['academic'])) {
$academic=$_GET['academic'];
echo '<input type="text" name="academic" class="form-control" required value='.$academic.'>';
# code...
}
else
{
echo '<input type="text" name="academic" class="form-control" required>';
}
?>
</div>
<div class="col-lg-4">
<label for="year_level">Year Level</label>
<?php
if (isset($_GET['year'])) {
$year=$_GET['year'];
echo '<input type="text" name="year" class="form-control" required value='.$year.'>';
# code...
}
else
{
echo '<input type="text" name="year" class="form-control" required>';
}
?>
</div>
<div class="col-lg-4">
<label>OR Number</label>
<?php
if (isset($_GET['or'])) {
$or=$_GET['or'];
echo '<input type="text" name="or" class="form-control" required value='.$or.'>';
# code...
}
else
{
echo '<input type="text" name="or" class="form-control" required>';
}
?>
</div>
</div>
<br>
<div class="row">
<div class="col-lg-4">
<label>First Name</label>
<?php
if (isset($_GET['firstname'])) {
$firstname=$_GET['firstname'];
echo '<input type="text" name="firstname" class="form-control" required value='.$firstname.'>';
# code...
}
else
{
echo '<input type="firstname" name="firstname" class="form-control" required>';
}
?>
</div>
<div class="col-lg-4">
<label>Last Name</label>
<?php
if (isset($_GET['lastname'])) {
$lastname=$_GET['lastname'];
echo '<input type="text" name="lastname" class="form-control" required value='.$lastname.'>';
# code...
}
else
{
echo '<input type="text" name="lastname" class="form-control" required>';
}
?>
</div>
<div class="col-lg-4">
<label>Middle Initial</label>
<?php
if (isset($_GET['middle'])) {
$middle=$_GET['middle'];
echo '<input type="text" name="middle" class="form-control" required value='.$middle.'>';
# code...
}
else
{
echo '<input type="text" name="middle" class="form-control" required>';
}
?>
</div>
</div><!--End of Second row-->
<br>
<button class="btn btn-primary btn-block" type="submit" name="register">Register</button>
</form>
Here is the php code that checks and gets the inputted data from the form
if (isset($_POST['register'])) {
# code...
$year_level=$_POST['year'];
$academic_year=$_POST['academic'];
$or_number=$_POST['or'];
$stud_fname=$_POST['firstname'];
$stud_lname=$_POST['lastname'];
$stud_mi=$_POST['middle'];
$or_check_query="SELECT * FROM tbl_user WHERE or_number=$or_number";
$result=mysqli_query($conn,$or_check_query);
$or=mysqli_fetch_assoc($result);
if($or['or_number']===$or_number) {
header("Location: index.php?signup=failed&academic=$academic_year&year=$year_level&or=$or_number&firstname=$stud_fname&lastname=$stud_lname&middle=$stud_mi");
# code...
}
else {
$sql= "INSERT INTO tbl_user(or_number,academic,year,firstname,lastname,middle)
VALUES ('$or_number','$academic_year','$year_level','$stud_fname','$stud_lname','$stud_mi')";
mysqli_query($conn,$sql);
header("Location: index.php?signup=success");
}
}