diff --git a/library/src/calculator_functions.cpp b/library/src/calculator_functions.cpp
index 0b085c4..9c9bed8 100644
--- a/library/src/calculator_functions.cpp
+++ b/library/src/calculator_functions.cpp
@@ -1940,9 +1940,9 @@ QList<int> Calculator::GetTimeSteps(Configuration *cfg, int paymentOptionIndex)
     return m_timeSteps[paymentOptionIndex];
 }
 
-uint32_t Calculator::GetPriceForTimeStep(Configuration *cfg, int timeStep) const {
+uint32_t Calculator::GetPriceForTimeStep(Configuration *cfg, int timeStep, int paymentOptionIndex) const {
 
-    int const pop_id = cfg->getPaymentOptions().pop_id;
+    int const pop_id = cfg->getPaymentOptions(paymentOptionIndex).pop_id;
 
     for (auto[itr, rangeEnd] = cfg->PaymentRate.equal_range(pop_id); itr != rangeEnd; ++itr)
     {