Rude manager

Last month it was my mother's birthday so as a family we had to buy appliances for her. I bought my mother a stove with an oven aswell as pots in Shoprite Bellville so it happened that my sister also bought the same things. I work outside of Cape Town sometimes so because i was away and had the receipts with me we could not refund what i bought. On Friday i took the things back @Shoprite Phillipi and was met with such bad behavior from a lady who said her name was Erica and she said she was the manager. I asked why cant she accept the things as they are still in a box and i had the receipt as proof she said she won't take it back why dont i return where i bought it i found that strange as i asked before i made the purchase they said i can take it back to any Shoprite. The way the manager went on was so distasteful saying that im in her store she will do as she pleases she said she doesn't care what i think or feel. If this is how your stuff more especially those in managerial positions treat your customers then its a shame as i dont think ill ever go back and ill make sure that my family and friends are not to go shop there as customer service is not valued. Im stuck with things i dont need because your managers assist according to their feelings not policy