I have main report with parameter called list_departments: <parameter name="list_departments" class="java.util.Collection" nestedType="java.lang.String" evaluationTime="Early"> <defaultValueExpression><![CDATA[new ArrayList(Arrays.asList(new String[]{}))]]></defaultValueExpression></parameter> Generating a report through the jasper studio works fine. But when deploy it on server, i have problem with rest /rest_v2/reportExecutions (code written in python - flask): payload = { "reportUnitUri": "my_name", "async": True, "outputFormat": "pdf", "interactive": True, "ignorePagination": False, "parameters": { "reportParameter": [{"name": "list_departments", "value": ["val1","val2"]},...] } } All other parameters are well processed and displayed on the report except this one, which is displayed as an empty list, although something has been sent (val1, val2). Cannot find out where the problem is occurring, please help