Incorrect pricing

On, Feb 1 2021 I had an experience at Eersteriver Super Spar in fact I always have an bad experience at this store since they have opened their doors especially with their customer service. I always let it slide however this time I feel my issues should be addressed. I was at the store on 1 Feb 2021, I had to issues which I'd like to address. I was going to let it slide but when I checked my slip and realized I paid more for something that was advertised as R7.99 on the shelf. Also, I stood in a line and the cashier cashier first decided to buy a whatsapp bundle for herself before helping me after her colleague told her she should wait cause she has a customer waiting but she still went ahead and made her purchase. Tersia Damons at the cigarette counter then called me and assisted me and I received great service from her. She saw it fit to call me and assist me which she didn't need to do but she did and I need to compliment her on her great service. I bought 2 x Spar Wine Gums and 1 x Fruit Pastill. On the self it showed R7.99 but on my slip it scanned R19.99 which I saw now when I checked the slip. I am utterly disappointed. Since I've started purchasing at your store I've always left unhappy about something. Yesterday I was there too, none of the staff on the floor is eager to assist in anyway. They'll see a customer battling but they won't offer any sort of assistance. Please advise. I tried contacting the store on the same day via their Facebook social media platform and to date I have received no response.