Baddest customer services of my life at Woolworths

Baddest customer and unprofessional service of my life. The way I have been treated, after that I have my account more then 10 years and never skipped any installment. For so long felt like a loyally customer, but now I feel like closing my account at Woolworths.

I bought myself a pair (size 12) flip-flops at Woolworths Secunda on 24 November 2019 and went home and at home I put them on to make sure that they fit for me, I then realize that I may have to get me a size 13. So yesterday I went to Menlyn Mall's WoolWoolworths to go and change it. Then my baddest customer experience started, they told me that they will refuse to refund me (they also didn't had a size 13) because the flip-flop's have a little dust on it, I told them I had them on then I realized that it doesn't fit me then I took them off. But they say they would change it or refund me. I went to complain to the manager (manager of customer service department) after the staff at the customer department inside of the shop also refuse. I went to another manager inside the shop I complain to him, he told me that they have no reanson to refuse me (he also looked at the flip-flops) but he said that he can't help me because he is the manager at bothroom department.