Switching between front and rear camera the viewfinder is freezing. Is there a solution to this? In Photo mode 3x zoom is using main lens. Why is this not using telephoto?

Hi, Is anyone getting the promised exchange bonus? When I purchased on Samsung shop they were showing Rs 8000 exchange bonus but Cashify did not add that amount in case of deffered exchange. Now after 3 weeks of followup Samsung is not providing any ...