diff --git a/Simulation/ISF/ISF_FastCaloSim/ISF_FastCaloSimEvent/src/TFCSONNXHandler.cxx b/Simulation/ISF/ISF_FastCaloSim/ISF_FastCaloSimEvent/src/TFCSONNXHandler.cxx
index e57fdc3fd3464141f66f6551c67167205dcb179e..92b1c513fd0af61dc58cb4dfb9d23b7949d16944 100644
--- a/Simulation/ISF/ISF_FastCaloSim/ISF_FastCaloSimEvent/src/TFCSONNXHandler.cxx
+++ b/Simulation/ISF/ISF_FastCaloSim/ISF_FastCaloSimEvent/src/TFCSONNXHandler.cxx
@@ -324,7 +324,7 @@ void TFCSONNXHandler::writeBytesToTTree(TTree &tree,
 void TFCSONNXHandler::readSerializedSession() {
   ATH_MSG_DEBUG("Transforming bytes to session.");
   Ort::Env env(ORT_LOGGING_LEVEL_WARNING, "test");
-  Ort::SessionOptions opts({nullptr});
+  Ort::SessionOptions opts{nullptr};
   m_session =
       std::make_unique<Ort::Session>(env, m_bytes.data(), m_bytes.size(), opts);
   ATH_MSG_DEBUG("Transformed bytes to session.");