Bad service and inconsiderate staff

My daughter whose 3months was admitted in hospital just opposite the mall where this store is located. Unable to express milk, my parents buy me a NUK manual breast pump. There was no mention that you purchase at your own risk or that it is not returnable. The pump is stuck and would not move and if it did it was with great difficulty. On being discharged from hospital with proof of purchase i returned the pump. A customer service lady by the name of Zanele explains that for hygienic purposes they cannot except and then proceeds to call a manager and explain and he from a distance tells her she should call a floor sales person he will not exchange nor refund. They then proceed to have their own conversation laughing over the phone. The manager Phillip and Zanele continue with their own conversation with other and not informing me. Zanele then proceeded to talking with other cashiers and leaving me standing by the counter with an aircon over us and did not even offer a chair. After a while when I asked if anybody was to assist me, another consultant at the counter then calls Philip the manager who says he is busy with something else and cannot attend to me. He has other things.