diff --git a/openbis_standard_technologies/dist/core-plugins/eln-lims/1/as/initialize-master-data.py b/openbis_standard_technologies/dist/core-plugins/eln-lims/1/as/initialize-master-data.py
index 7bb0dbf55934411c0ea5073d4696f8bdeb61d601..e3eaee0601ed6c89d3e53f6372cf7ed6e572ce6a 100644
--- a/openbis_standard_technologies/dist/core-plugins/eln-lims/1/as/initialize-master-data.py
+++ b/openbis_standard_technologies/dist/core-plugins/eln-lims/1/as/initialize-master-data.py
@@ -25,7 +25,7 @@ helper = MasterDataRegistrationHelper(sys.path)
 api = CommonServiceProvider.getApplicationContext().getBean(ApplicationServerApi.INTERNAL_SERVICE_NAME)
 sessionToken = api.loginAsSystem()
 props = CustomASServiceExecutionOptions().withParameter('xls', helper.listXlsByteArrays())\
-    .withParameter('xls_name', 'ELN-LIMS').withParameter('update_mode', 'IGNORE_EXISTING')\
+    .withParameter('xls_name', 'ELN-LIMS').withParameter('update_mode', 'UPDATE_IF_EXISTS')\
     .withParameter('scripts', helper.getAllScripts())
 result = api.executeCustomASService(sessionToken, CustomASServiceCode("xls-import-api"), props);
 print("======================== master-data xls ingestion result ========================")