diff --git a/src/utils.cpp b/src/utils.cpp
index 31854b2..9496db3 100644
--- a/src/utils.cpp
+++ b/src/utils.cpp
@@ -118,7 +118,7 @@
     {
         std::ostringstream ss;
         std::transform(type.m_unionTypes.begin(), type.m_unionTypes.end(), std::experimental::make_ostream_joiner(ss, ", "), [this](const auto& unionType) {
-            return std::visit(*this, unionType);
+            return std::visit(*this, unionType.m_type);
         });
         return ss.str();
     }