Cron inside a plugin

Hello, I am working on a plugin that imports data every hour if there are new files to process. I am trying to use wp_schedule_event and it does not fire the function.

/**
 * Plugin activation
 */
 function gpi_saxo_activation() {
	wp_schedule_event( time(), 'hourly', 'gpi_saxotech_import');
}
register_activation_hook(__FILE__, 'gpi_saxo_activation');
add_action('gpi_saxotech_import', 'gpi_hourly_import');

/**
 * Plugin deactivation
 */
function gpi_saxo_deactivation() {
	wp_clear_scheduled_hook('gpi_saxotech_import');
}
register_deactivation_hook(__FILE__, 'gpi_saxo_deactivation');

/**
 * GPI hourly import
 */
function gpi_hourly_import() {
	$xml_files = '';
	//$xml_files = gpi_get_all_files();

	if($xml_files) {
		//$parsed = gpi_parse_xml($xml_files);
		wp_create_category('Successfully created XML file');
	} else {
		wp_create_category('WFailure to create XML file');
	}
}

Can someone give me an idea to what is wrong?