Lost my oportunity to stand a chance to win a car

I discovered that people are been cheated there entries with some of the promotions/competition from the stores we buying from. Cashiers are *****ing our entries till slips right in front of us and we don't notice. I went to Shoprite Roodepoort 18-11-2017 and i bought participating products for a win a car competition with Shoprite Roodepoort. After paying for the items, i was suppose to get 3 entries (3 entire slips with unique codes) as per the till slip received but i was only provided with (1 entire slips with unique codes). As the entries slips were coming out from the machine, cashier quickly garbed and squashed my entries as they com off the machine as they meant nothing but i noticed that those were my entries that she took right in from of my eyes. I believe she have been keeping a lot of this entries for her self from a very honest regular costumers like me. I now have 4 entries and i was cheated my 2 more entries, maybe those were my lucky final entries that she took. I still have all entries and proof that i was suppose to get 3 entries which she stole from me. We spending money to earn those entries but what just happened to me was so unfair and hope something will be done about my issue. I now decided to send this complain today as the same thing happened to my best colleague at Randburg Checkers Bram Fischer lunch time today. Guys kindly have all Cashiers trained on what they should and shouldn't do as this is now affecting your stores. I'm not doing this because i also wish to win one day but customers should be treated right and fair #******* must fall, People who bite the hand that feeds them usually lick the boot that kicks them.