Poor clothing quality

I bought a Jacket for my Son last week Wednesday on the buy 2 get 2 sale at Johannesburg Cbd Edgars.. He wore it twice,the buttons are already falling off…iam really concerned on about the quality of your clothing…i swiped using my debit card, but unfortunately i dont have the receipt anymore ….i would love to have an exchange or a refund for this, there is no way ,,,a jacket worth R400( sale price) to have such quality? Very dissapointing