diff --git a/src/apify_client/clients/resource_clients/actor.py b/src/apify_client/clients/resource_clients/actor.py
index 675783c4..c9b206dc 100644
--- a/src/apify_client/clients/resource_clients/actor.py
+++ b/src/apify_client/clients/resource_clients/actor.py
@@ -701,7 +701,7 @@ async def start(
             memory=memory_mbytes,
             timeout=timeout_secs,
             waitForFinish=wait_for_finish,
-            forcePermissionLevel=force_permission_level,
+            forcePermissionLevel=force_permission_level.value if force_permission_level is not None else None,
             webhooks=encode_webhook_list_to_base64(webhooks) if webhooks is not None else None,
         )