diff --git a/reportservice/manual_run.py b/reportservice/manual_run.py
index 7e852bcb72e92fa9a7f597978a15bf9602beda84..5a31f1e0a4b2d978691e0780c1d963e8fa23e39b 100644
--- a/reportservice/manual_run.py
+++ b/reportservice/manual_run.py
@@ -37,7 +37,7 @@ def manual_run(req_instr):
     logging.info('{} Manual Run'.format(msg))
 
 arg_parser = argparse.ArgumentParser(description='Manual Launch')
-arg_parser.add_argument('--req-instr', default='all', nargs='+')
+arg_parser.add_argument('--req-instr', default=['all'], nargs='+')
 arg_parser.add_argument('--config-file', type=str, default='./report_conf.yaml')
 arg_parser.add_argument('--log-file', type=str, default='./report.log')
 arg_parser.add_argument('--logging', type=str, default="INFO",