Undefined index IN PHP SESSION? [duplicate] - php

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"Notice: Undefined variable", "Notice: Undefined index", "Warning: Undefined array key", and "Notice: Undefined offset" using PHP
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Closed 2 years ago.
I have this code in my login.hmtl in s section with ajax method:
$.ajax ({
type:'post',
url:'Controladores/login.php',
data:{do_login:"do_login", nick:nick, pass:pass },
success:function(response) {
alert($.trim(response));
if ($.trim(response) ==='Correcto'){
window.location.href="intranet.php?ruta=inicio";
return false;
}
else{
alert('Datos incorrectos. Volver a intentar.');
}
}
});
This redirects me to login.php where I connect to the database and then check if the username and password are correct. If they are, they return an answer Correct or Incorrect.
Here is the main part where I start my session, and also if username and password match, set the username 'NICK' to the session.
session_start();
$db = new Conexion();
$conn = $db->connect( '00.00.00.00', 'Seguridad');
$param = [$nick, $pass];
$query = "exec Seguridad.dbo.autenticacion ?, ?";
$result= $db->rows($conn, $query, $param);
$obj = json_decode($result);
//echo $obj[0]->resultado;
if( $obj[0]->resultado ='Correcto' ){
$_SESSION['nick']= $nick;
$_SESSION['nombreusuario'] = $obj[0]->nombreusuario;
$_SESSION['agencia'] = $obj[0]->CodigoAgencia;
echo ("Correcto");
}else{
if ($obj[0]->resultado =='Incorrecto'){
echo ("Incorrecto");
}
}
Then, In my home page called inicio.php I called again the session but the message is:
Notice: Undefined index: nick in C:\xampp\htdocs\intranetv3\Vistas\modulos\inicio.php on line 3
<?php
session_start();
$userName = $_SESSION['nick'];
echo "$userName";
?>
I have read other article but have not found anything.
I checked if the answer Correct or Incorrect returns the answer and it returns.
I printed the user name and password. It worked.
I also printed the $_SESSION['nick'], I see it has the username.
Apparently when I go to my inicio.hmtl the session just unssets or something, I have no idea what might be wrong. Please HELP!!