Disgusting service

Good day Please assist me, I buy at Shoprite U save 18680 hinterland street Mamelodi East because its near my home. I normally use debit card but the past month i was using cash and i noticed that they don't give 10 cents change, I asked the cashier who had no name badge why she didn't give me my 10 cents and whether will she sell to me when I'm short by 10 cents, she laughed and said yes. The next time I went another cashier with no name badge gave me my change but short by 10 cents, I asked her too why she just said rudely she'll give it to me and she did. Then I asked for the Manager a male approached me, he was holding a file on his chest couldn't see name badge. I explained my issue, he apologized and said he wasn't aware of it and he will sort it out. I went again today and again I was not given my full change, short by 10 cents. I asked this cashier why and she acted as if she wasn't aware, I called the manager a lady came but no name badge. I explained the matter she said that all cashiers where given 10 cents in their tills and wasn't aware of this behaviour. She apologized and said she would sort it out, but I don't see it happening. How many customers are being ***** by these cashiers, disciplinary action must be taken towards these cashiers. They are making personal money from customers that's theft that why they all don't have name badges and the receipts has no cashier name, 100 customers per cashier paying cash is R10. It may look little as a 10 cents but times it a day,week, month and year. The thing is if I go the short by 10 cents after being ****** by them regularly they will not allow to sell to me. I'm so disgusted by their service