Shaban

Hi I have Nissan Note E-Power 2018 Model in Pakistan. I'm observing that its generator frequently starts & car is less shifting on a pure battery run. That is why my mileage drops down to 10km/Ltr from 20Km/Ltr. Temperature in these days is 40-45C here, but last year i did not faced such issue inspite of same high temperature. Please guide? regards