diff --git a/scaleway-async/scaleway_async/iam/v1alpha1/api.py b/scaleway-async/scaleway_async/iam/v1alpha1/api.py
index bda1d9028..a780d75d2 100644
--- a/scaleway-async/scaleway_async/iam/v1alpha1/api.py
+++ b/scaleway-async/scaleway_async/iam/v1alpha1/api.py
@@ -594,8 +594,9 @@ async def update_user_username(
         username: str,
     ) -> User:
         """
-        :param user_id:
-        :param username:
+        Update an user's username. Private Beta feature.
+        :param user_id: ID of the user to update.
+        :param username: The new username.
         :return: :class:`User <User>`
 
         Usage:
diff --git a/scaleway-async/scaleway_async/iam/v1alpha1/types.py b/scaleway-async/scaleway_async/iam/v1alpha1/types.py
index 8fde1d509..9dcc64737 100644
--- a/scaleway-async/scaleway_async/iam/v1alpha1/types.py
+++ b/scaleway-async/scaleway_async/iam/v1alpha1/types.py
@@ -1997,5 +1997,11 @@ class UpdateUserRequest:
 @dataclass
 class UpdateUserUsernameRequest:
     user_id: str
+    """
+    ID of the user to update.
+    """
 
     username: str
+    """
+    The new username.
+    """
diff --git a/scaleway/scaleway/iam/v1alpha1/api.py b/scaleway/scaleway/iam/v1alpha1/api.py
index 02675de26..fc4e0b269 100644
--- a/scaleway/scaleway/iam/v1alpha1/api.py
+++ b/scaleway/scaleway/iam/v1alpha1/api.py
@@ -594,8 +594,9 @@ def update_user_username(
         username: str,
     ) -> User:
         """
-        :param user_id:
-        :param username:
+        Update an user's username. Private Beta feature.
+        :param user_id: ID of the user to update.
+        :param username: The new username.
         :return: :class:`User <User>`
 
         Usage:
diff --git a/scaleway/scaleway/iam/v1alpha1/types.py b/scaleway/scaleway/iam/v1alpha1/types.py
index 8fde1d509..9dcc64737 100644
--- a/scaleway/scaleway/iam/v1alpha1/types.py
+++ b/scaleway/scaleway/iam/v1alpha1/types.py
@@ -1997,5 +1997,11 @@ class UpdateUserRequest:
 @dataclass
 class UpdateUserUsernameRequest:
     user_id: str
+    """
+    ID of the user to update.
+    """
 
     username: str
+    """
+    The new username.
+    """