Complain

I bought a phone from Ackermans on Saturday and when I got home i noticed that it was not the phone i really wanted. I wemt there this morning to return it amd the employees and their manager were rude and shouted at me and my father. They told us that they can not accept the phone unless if it has technical issues but when we read the terms and conditions they did not say that instead they said that we must return the phone in less than 7 days even if it does not have technical problems. Please help me im not happy or satisfied with what happened i really need to return this phone by tomorrow.