Baby City Pavilion refused to accept an unused iterm within 7days of purchase

Good Day I am writing this in disappointment and anger about the treatment I recieved at BABY city this Friday around 11am when I return an unused iterm. I purchased a maternity comfort pillow last Sunday afternoon for my sister and she said the shape is not the one she wants without even taking it out of the bag. Although I bought it with a dirty bag as all others in their shelves, but did not think they can sell dirty BABY iterm and knowing that I cannot open it before payment. I took it paid and left. The very rude and chiky managers of which one of them didn't even pay attention to us refused to accept it and claimed it's been used and I should've opened it and check if it's clean whilst there's no sign says that, also should've returned it the following day after purchase whilst the receipt states I have seven days to return iterm, well I did tell her I didn't have time to come to the mall during the and she rep**** as that's not her problem. When I asked them to open one in store and compare cleanliness they refused and said it will get dirty they can't take it out of the bag, telling me at same time I should've opened and check before purchasing but they don't want to do it in front of me. I then left the iterm with receipt instore and demanded my refund which they refused to give back. I asked for head office number and spoke to Rosh whom also surprisingly already new about my complaint before I can even explain, she was also rude and told me they'll not accept it when I asked why she just said "thank you goodbye". To avoid coursing a sin I chose to leave the store without my iterm and take legal action against them. I would highly appropriate if this matter is taken up and justice being served as i need my money back. Your prompt response would be appreciated not just for me but for the rest of unfairly treated customers but their management.