Mocked and humiliated at shoprite by its staff

Yesterday around 5 in the evening I went to shoprite jabulani mall to do my shopping.i then bought the R100 combo that comes with meal meal,rice,soya,macaroni and cooking oil and some little more things.i then proceed to a till to pay..but to my shock,I get to the till nd the guy who was helping me tells me that it's not giving me discount as I took the wrong cooking oil so I need to go change...I left everything and went to go get the correct one but reaching to the till still promo did not scan,and he was now joined by a colleague.i was ordered to go fetch the correct rice (and I asked which is the correct one?)both the tellers started laughing saying broke people r boring.i should go look for work so I can go fill up trollies like other people.i became a joke to them as they were there laughing about my poverty instead of helping me get the right things.they never cared about anything or helping me.im so very dissatisfied with the service I got there.