diff --git a/src/Picqer/Financials/Moneybird/Entities/Subscription.php b/src/Picqer/Financials/Moneybird/Entities/Subscription.php
index 2bf2e52..0f6a606 100644
--- a/src/Picqer/Financials/Moneybird/Entities/Subscription.php
+++ b/src/Picqer/Financials/Moneybird/Entities/Subscription.php
@@ -38,6 +38,7 @@ class Subscription extends Model
         'prices_are_incl_tax',
         'subscription_prices_are_incl_tax',
         'subscription_products',
+        'recurring_sales_invoice_id',
     ];
 
     /**