Hirsch’s fridge and customer service

I ordered a fridge online and was told by delivery staff that I had 7 days to return it as long a I kept the plastic wrapping on and all other packaging. After 48 hrs and having switched it on Hirsch’s were not willing to exchange it for a larger more expensive fridge. Poor customer services and no solution offered. I am taking further business elsewhere and now have to sell brand new fridge at a loss.