diff --git a/libraries/libstratosphere/source/os/impl/os_waitable_manager_target_impl.os.horizon.hpp b/libraries/libstratosphere/source/os/impl/os_waitable_manager_target_impl.os.horizon.hpp
index 44cb6f138..46c13d3b7 100644
--- a/libraries/libstratosphere/source/os/impl/os_waitable_manager_target_impl.os.horizon.hpp
+++ b/libraries/libstratosphere/source/os/impl/os_waitable_manager_target_impl.os.horizon.hpp
@@ -21,7 +21,7 @@ namespace ams::os::impl {
 
     class WaitableManagerHorizonImpl {
         public:
-            static constexpr size_t MaximumHandleCount = static_cast<size_t>(ArgumentHandleCountMax);
+            static constexpr size_t MaximumHandleCount = static_cast<size_t>(ams::svc::ArgumentHandleCountMax);
         private:
             Handle handle;
         private: