Terrible attitude

I bought a pair of sandles from the East Rand Mall branch and less than a month later, the strap breaks. So upon exchanging them, a man whom i assume is part of the security, stops me and refuses to let me exchange the shoes, says i can just fix the strap myself. Never have i been so humilated and disrespected. All i wanted was to exchange my shoes, and this man who i would assume has no say with regard to the clothing, verbally attacks me. I am absolutely disgusted! And if this is how you treat your customers, then i won't be shopping there again!