diff --git a/cli/openbb_cli/argparse_translator/argparse_translator.py b/cli/openbb_cli/argparse_translator/argparse_translator.py
index 812aba22890..dfad536460d 100644
--- a/cli/openbb_cli/argparse_translator/argparse_translator.py
+++ b/cli/openbb_cli/argparse_translator/argparse_translator.py
@@ -316,7 +316,7 @@ class ArgparseTranslator:
         if origin is list:
             return "+"
 
-        if origin is Union and any(
+        if origin in (Union, types.UnionType) and any(
             get_origin(arg) is list for arg in get_args(param_type)
         ):
             return "+"
diff --git a/cli/tests/test_argparse_translator.py b/cli/tests/test_argparse_translator.py
index 65306795f48..0fb366574e1 100644
--- a/cli/tests/test_argparse_translator.py
+++ b/cli/tests/test_argparse_translator.py
@@ -497,7 +497,7 @@ def test_list_nargs():
     actions = {action.dest: action for action in parser._actions}
 
     assert actions["symbols"].nargs == "+"
-    assert "values" in actions
+    assert actions["values"].nargs == "+"
 
 
 def test_custom_type_flattening():