not receiving email when form is submitted for otp

Hi Team

I dont have errors i have debugged the application, basically what i am trying to do. When before submiting a form, the form should hold until a user receive an email has an otp, so that can insert and continue. Problem i am experience i am not receiving an email.Maybe its something i am missing, setup everything from the phpmailer because it is working for registering users to the site. 

// forgot-password.php

// otp-confirmation.php

prepare($sql);
    $stmt->bind_param("s", $email);
    $stmt->execute();
    $result = $stmt->get_result();

    if ($result->num_rows == 1) {
        // Generate a random OTP and store it in the session
        $otp = rand(100000, 999999);
        $_SESSION['otp'] = $otp;
        $_SESSION['email'] = $email;

        // Send an email to the user with the OTP
        $mail = new PHPMailer;
        $mail->isSMTP();
        $mail->SMTPDebug = 0;
        $mail->Host = 'smtp.outlook.com';
        $mail->Port = 587;
        $mail->SMTPSecure = 'tls';
        $mail->SMTPAuth = true;
        $mail->Username = '[email protected]';
        $mail->Password = '***';
        $mail->setFrom('[email protected]', 'Your Name');
        $mail->addAddress($email);
        $mail->Subject = 'Password reset OTP';
        $mail->Body = 'Dear user,

Your OTP to reset your password is: ' . $otp;
        $mail->AltBody = 'Dear user, your OTP to reset your password is: ' . $otp;
        $mail->isHTML(true);
        if (!$mail->send()) {
            $error = 'Error: ' . $mail->ErrorInfo;
        } else {
            // Redirect the user to the OTP verification page
            header("Location: verify_otp.php");
            exit();
        }
    } else {
        // If the email does not exist in the database, display an error message
        $error = "Email not found. Please try again.";
    }
}


?>