Refuse to Exchange

I bought shoes from Tekkie Town at Wonder Park mall PTA and I bought the wrong size, then I went to another branch in Pretoria CBD at Vanderwalt street Sammy Marks and the pregnant Supervisor by the name of Bridget refused to exchange for me because I did not buy the shoes at their branch. We argued for 30 minutes as I saw the shoes were there and she said she didn't have it in stock/on her system , she told her staff members not to assist me as I have attitude but another member came to my rescue and she exchanged for me. I don't think I will ever buy shoes at Tekkie Town ever again . I would rather go to Sport scene, Cross trainer or Total sports as they have a great service. Please management talk to your staff members