Poor service

I bought a 12size sandal for my daughter on the 15th of December at Westgate, got home and when she fitted the shoe it was small, so i needed a bigger size and realised that i have misplaced my slip, since I bought with my debit card i was refises the exchange even when i had the product in good condition, just because i did not have a size, Rage is the only store that cannot make an exchange without a slip, i really received bad treatment regarding this issue i still have the message to show i had paid at rage but no reports are kept for duplicate reason, i regret being a customer to Rage and i would never encourage anyone to go to the ragr store thats how poor their service is.... Bad shopping