diff --git a/public/typo3conf/ext/ep_products/Classes/Service/ContingentImportService.php b/public/typo3conf/ext/ep_products/Classes/Service/ContingentImportService.php
index 36317548..7b2c2dbd 100644
--- a/public/typo3conf/ext/ep_products/Classes/Service/ContingentImportService.php
+++ b/public/typo3conf/ext/ep_products/Classes/Service/ContingentImportService.php
@@ -268,7 +268,7 @@ class ContingentImportService implements SingletonInterface, LoggerAwareInterfac
                 if (in_array($roomCode, $this->ignoredRoomTypes, true)) {
                     continue;
                 }
-                $roomTypeBusProId = $roomType['link'] ?? $roomType['idBusPro'];
+                $roomTypeBusProId = $roomType['link'] ?: $roomType['idBusPro'];
                 $xpath = sprintf('zimmerliste/zimmer[@idbuspro="%d"]', $roomTypeBusProId);
                 $xmlRoom = $xmlDate->xpath($xpath)[0];
                 $this->calculateContingent($xmlRoom, $roomType, $date, $hotelData);