diff --git a/lib/Citycom/OanApiHelper.php b/lib/Citycom/OanApiHelper.php
index ee793e0e8..d6765c314 100644
--- a/lib/Citycom/OanApiHelper.php
+++ b/lib/Citycom/OanApiHelper.php
@@ -162,7 +162,7 @@ class Citycom_OanApiHelper {
             if(!in_array($stype->name, $want_services)) continue;
 
             $ctag = $ctags[$service_count];
-            $ctag_service_type = array_flip(CITYCOM_OAN_API_SERVICES_FOR_ORDER)[$stype->name];
+            $ctag_service_type = array_flip($allowed_service_types)[$stype->name];
             if(!$ctag_service_type) {
                 $this->log->error(__METHOD__.": Cannot create Service ".$stype->name." for preorder ".$preorder->id." because no ctag service type defined");
                 return false;