Bad customer service

I am very disappointed and ****ed with the treatment by Russells Pretoria Acardia more especially by the consultant named Helen. I have been buying from the very same store from 2018 and last week I saw a Power station and went to the same store to make a purchase and I got the item. Before I make a purchase a sent the email enquiring about the item, I never got a reply, I went to the store and enquire about the item and the same lady I bought the power station from called Helen had no information about the item, the whole team had no information, they I made a purchase, getting home finding out that the item is weak, has no lasting power and it doesn't do what it's supposed to do.

Yesterday 18 December, I went to the store to get a refund and the lady (Hellen) refused to refund me telling that Russells is not a Pawnshop. How on earth does appliances or electronics doesn't get a refund if a customer is not happy with it.