How to insert time and date in database when user login on site(login tracking)?

login tracking

 if(function_exists('date_default_timezone_set')) {
date_default_timezone_set("Asia/Kolkata");
}

$date = date("d/m/Y");
$time =  date("H:i a");
global $wpdb;
$table_name = $wpdb->prefix . "logintime";
$wpdb->insert($table_name, array('start_time' => $date, 'login_date' => $time) );