Wrong shoe size delivered no apology and no response in fixing it

A few months ago my mother saw the shoes I had been looking for as she shops on one day only a lot and she offered to buy then and then I would reimburse her, Crocs Dylan Clogs. we placed the order, imagine my disappointment of recieving a shoe written a size 8 when in actual fact that I had ordered a size 7, the packaging was written a size 7 but the shoe was a size 8.. these being men sizes as a woman there was no way this would've fit me they were so big that they left space at the back..

In logging I requested that I am brought the correct size as per the packaging, only for a lady called Ntokozo to respond and tell us there was no mistake as these were UK sizes assuming I have never bought Crocs shoes and I wouldn't know what my shoe size is..

There was no apology nor explanation and she ignored and I am trying to figure out if they are telling me a shoe written a size 7 doesn't exist and they would know my show size better than myself