public function getSubscriptionInvoices(int $subscriptionId): array
    {
        $results = $this->_createInvoiceQuery()
            ->where(['subscriptionId' => $subscriptionId])
            ->orderBy(['dateCreated' => SORT_DESC])
            ->all();

        $invoices = [];

        foreach ($results as $result) {
            $result['invoiceData'] = Json::decodeIfJson($result['invoiceData']);
            $invoices[] = new Invoice($result);
        }

        return $invoices;
    }