Insults hurled at a staff member and customer

As a petite, young black woman, I often get bad service & the general assumption is that I'm a student & I won't complain. This was the case on Friday, 13/02/15 when I went to my Spar to get my daily supplies. As the lady at the till was giving me change, the supervisor came & started shouting & hurled insults at the till lady for the kind of change she was giving me. As I tried to intervene, she turned around & hurled insults at me. When I asked her for her name & for the manager, she in disinterest pointed in a random direction. I eventually found the manager Casandra who listened to my complaint & assured me that I'd get feedback & an apology the following day as I was humiliated & belittled in front of fellow customers. When I went to shop the next day, I literally had to chase after Casandra, who was not so friendly this time as she was outside the store. She insisted yet again that she'd contact me by Sunday afternoon. When I went there this evening to do my Sunday shopping, she point blank ignored me & looked in the other direction. Clearly she hasn't resolved the matter & has no interest in doing so. I use this Spar daily & refuse to be treated in this manner. \MY SPAR":-("""