School uniform exchange decline

On the 9 January 2022 I sent my elder son to to buy school uniform for both him and his younger brother as I was working on the day, I wanted them to fit the uniform in store however they were told that no fitting allowed. when they got home the uniform was not fitting and my son tried taking it back on the 10/01/2022 he was told to come with his ID and his only 15years old. On the 11/01/2022 my mom went and was told that they not going to exchange for her because we lost the slip...people loose slips all the time for haven sake. And today my kids had to go back to school with old uninform from 2years back, I couldn't even bare the embarrassment my kids went through wen they saw their pears in new uniform what Pep Jabulani Mall did to me and my kids it's beyond repair this is a life time trauma on my kids. I need this uniform exchanged ASAP awaiting for respond.

thank you