在哪里验证密码是否需要PHP中的rehash？

I got the following code and nothing is getting inserted into my database and I can't figure out why.. is the password_needs_rehash() function at it's right spot?

I got a test where I echo out the new generated with a Javascript alert and it shows a new hash but the new hash is not getting inserted into the database. There must be a error in my logic but I can't find it.

<?php
session_start();
include 'mysqli.php';


$userID = strtolower($_POST['userID']);
$passwordFromForm = $_POST['password'];
$_SESSION['userID'] = $userID;

//Select the password from the requested userID and put into variable
$sql = "SELECT password FROM userdata WHERE userID = '$userID'";
$result = mysqli_query($conn, $sql);
$row = mysqli_fetch_assoc($result);
$passwordFromDatabase = $row['password'];

$verified = password_verify($passwordFromForm, $passwordFromDatabase);

if($verified == 0){
echo '<meta http-equiv="refresh" content="0; URL=index.php?triedLogin" />';

}else{

if(password_needs_rehash($passwordFromDatabase, PASSWORD_DEFAULT, ['cost' => 14])){

    $passwordFromDatabase = password_hash($passwordFromDatabase, PASSWORD_DEFAULT, ['cost' => 14]);

    echo "<script>alert('".$passwordFromDatabase."');</script>";

    $sql = "INSERT INTO userdata ('password') VALUES ('$passwordFromDatabase')";

    //NOW LOGIN WITH NEW PASSWORD
    $sql = "SELECT * FROM userdata WHERE userID = '$userID' AND password = '$passwordFromDatabase'";
    $result = mysqli_query($conn, $sql);

        if(!$row=mysqli_fetch_assoc($result)){
            echo '<meta http-equiv="refresh" content="0; URL=index.php?triedLogin" />';
        } else {
            $_SESSION['ID'] = $row['userID'];
            unset($_SESSION['userID']);
            echo '<meta http-equiv="refresh" content="0; URL=app/index.php" />';
        }

}else{

    $sql = "SELECT * FROM userdata WHERE userID = '$userID' AND password = '$passwordFromDatabase'";
    $result = mysqli_query($conn, $sql);

    if(!$row=mysqli_fetch_assoc($result)){
        echo '<meta http-equiv="refresh" content="0; URL=index.php?triedLogin" />';
    } else {
        $_SESSION['ID'] = $row['userID'];
        unset($_SESSION['userID']);
        echo '<meta http-equiv="refresh" content="0; URL=app/index.php" />';
    }
}
}
?>

• Make make sure your table field is large enough to hold that value because hash are very long, it will throw errors thus no INSERT.

• You should prepare your statements, I am surprised you don't do this yet you into password hashing.