diff --git a/reading_machine/src/Classifier.cpp b/reading_machine/src/Classifier.cpp
index 706f75727beb19943c8e49694849734e65549d45..33b9ee3370960bc4ddd38ee47c8cbff1e40d68ed 100644
--- a/reading_machine/src/Classifier.cpp
+++ b/reading_machine/src/Classifier.cpp
@@ -56,7 +56,7 @@ Classifier::Classifier(const std::string & name, std::filesystem::path path, std
             }
           }
         }))
-    util::myThrow(fmt::format("Invalid line '{}', expected '{}'\n", definition[0], "(LossMultiplier :) {state1,multiplier1 state2,multiplier2...}"));
+    util::myThrow(fmt::format("Invalid line '{}', expected '{}'\n", definition[1], "(LossMultiplier :) {state1,multiplier1 state2,multiplier2...}"));
 
   initNeuralNetwork(definition);
 }