fix error

Author: Sabrina Hernandez

PWGCF/Flow/Tasks/flowZdcTask.cxx

@@ -659,7 +659,7 @@ struct FlowZdcTask {
     float sumZNC = ((zdcread.energySectorZNC())[0] + (zdcread.energySectorZNC())[1] + (zdcread.energySectorZNC())[2] + (zdcread.energySectorZNC())[3]) / cfgCollisionEnergy;
     float sumZNA = ((zdcread.energySectorZNA())[0] + (zdcread.energySectorZNA())[1] + (zdcread.energySectorZNA())[2] + (zdcread.energySectorZNA())[3]) / cfgCollisionEnergy;
     float sumZPC = ((zdcread.energySectorZPC())[0] + (zdcread.energySectorZPC())[1] + (zdcread.energySectorZPC())[2] + (zdcread.energySectorZPC())[3]) / cfgCollisionEnergy;
-    float sumZPA = ((zdc.energySectorZPA())[0] + (zdc.energySectorZPA())[1] + (zdc.energySectorZPA())[2] + (zdc.energySectorZPA())[3]) / cfgCollisionEnergy;
+    float sumZPA = ((zdcread.energySectorZPA())[0] + (zdcread.energySectorZPA())[1] + (zdcread.energySectorZPA())[2] + (zdcread.energySectorZPA())[3]) / cfgCollisionEnergy;
     float sumZDC = sumZPA + sumZPC + sumZNA + sumZNC;
     float sumZEM = zdcread.amplitudeZEM1() + zdcread.amplitudeZEM2();
     float sumZNs{znA + znC};