Added the most records to the new table - php

Question

I'm trying to create an app. So the way an app like this.
Phone numbers that order more than five times, will enter the customer table.
This is the code I tried.
<?php
$con = mysqli_connect('localhost','root','','bus');
$sql = mysqli_query($con, "SELECT phone_number, count(phone_number) as quantity FROM report GROUP BY phone_number ORDER BY quantity");
while ($qq = mysqli_fetch_array($sql)) {
$quantity = $qq['quantity'];
if ($quantity == 5 ) {
$phone_number = $qq['phone_number'];
$quantity = $qq['quantity'];
$sql2 = mysqli_query($con, "SELECT phone_number FROM record WHERE EXISTS (SELECT phone_number FROM customer)");
$exe = mysqli_num_rows($sql2);
if($exe == 1){
echo"<script>window.location = 'show-customer.php';</script>";
}else{
$sql3 = mysqli_query($con, "INSERT INTO customer (`phone_number`) VALUES ('$phone_number')");
echo"Successful added";
}
}}
?>
Explanation of the code:
I counted the number of times the phone number was ordered.
If the phone number has been ordered five times, then I check that the phone number already exists or not on the customer table.
If it's there then I'll show the customer's page. If not then I will add that phone number to the customer table.
After I run my code, it only displays "Successful added" without any record in the table.
I'm really a beginner, and all the code above is my own idea.
I do not know, I made a big mistake or not in my code.
Please help, because I have to finish my final assignment in my college. :(

Answer 1

Change the following ($quantity = 5 ) to ($quantity == 5 )