diff --git a/lib/livebook/notebook/app_settings.ex b/lib/livebook/notebook/app_settings.ex
index 341cb478a..434e195cb 100644
--- a/lib/livebook/notebook/app_settings.ex
+++ b/lib/livebook/notebook/app_settings.ex
@@ -92,7 +92,7 @@ defmodule Livebook.Notebook.AppSettings do
       :output_type
     ])
     |> validate_format(:slug, ~r/^[a-zA-Z0-9-]+$/,
-      message: "slug can only contain alphanumeric characters and dashes"
+      message: "should only contain alphanumeric characters and dashes"
     )
     |> cast_access_attrs(attrs)
     |> cast_mode_specific_attrs(attrs)
diff --git a/lib/livebook/teams/org.ex b/lib/livebook/teams/org.ex
index 7efc68424..ef258aa3a 100644
--- a/lib/livebook/teams/org.ex
+++ b/lib/livebook/teams/org.ex
@@ -48,7 +48,9 @@ defmodule Livebook.Teams.Org do
     org
     |> cast(attrs, @fields)
     |> validate_required(@required_fields)
-    |> validate_format(:name, ~r/^[a-z0-9][a-z0-9\-]*$/)
+    |> validate_format(:name, ~r/^[a-z0-9][a-z0-9\-]*$/,
+      message: "should only contain alphanumeric characters and dashes"
+    )
   end
 
   @doc """