issue with password_verify() - php

Question

So i am a newbie in php.
I have database with a pseudo and pwd table, the passwords are crypted with password_hash.
This is how i send new user in my database :
<?php
$options = [
'cost' => 8,
'salt' => mcrypt_create_iv(22, MCRYPT_DEV_URANDOM),
];
$pwd = password_hash($pwd, PASSWORD_BCRYPT, $options);
$insert_query = "insert into user values ('$pseudo','$pwd','$mail')";
$mysqli->query($insert_query);
It's working, then when i want to log as user wich is in the database, i searh the password associated with the pseudo i write in the form, once i have the password i use it with the noon crypted password (the one i get by POST)
$options = [
'cost' => 8,
'salt' => mcrypt_create_iv(22, MCRYPT_DEV_URANDOM),
];
$pwd2 = password_hash($pwd, PASSWORD_BCRYPT, $options);
$sql_log = "select mdp from user where pseudo ='$pseudo'";
$mysqli->multi_query($sql_log);
if($res = $mysqli->use_result()) {
while($row = $res->fetch_row()) {
echo $row[0]."<br/>";
}
$res->close();
echo $pwd2."<br/>";
echo $pwd."<br/>";
if(password_verify($pwd,$row[0])) {
$mysqli->close();
$_SESSION['pseudo'] = $pseudo;
die("<script>location.href = 'homepage.php'</script>");
}
else
echo "putin";
}
But it's not working, ive read other topics about it but nothing helps me.

Answer 1

Ok i've found my problem, i don't know if it will be usefull for others or if i make understandable but i was really dumb.
while($row = $res->fetch_row()) {
echo $row[0]."<br/>";
}
$res->close();
echo $pwd2."<br/>";
echo $pwd."<br/>";
if(password_verify($pwd,$row[0])) {
$mysqli->close();
$_SESSION['pseudo'] = $pseudo;
die("<script>location.href = 'homepage.php'</script>");
}
i created row in the while and when i check his value out of the while it returns 0, so the second argument that i was passing in password_verify was null...
ty