Overcharged on online orders

I just want to give the people that order online a warning, please check your statement, invoices and your original confirmation emails when ordering online, i made a few orders on black Friday and cyber Monday, and on each order the overcharged me, the bag that's supposed to be free, they charge you for it, some of the items that was supposed to R159, they overcharged me, items that was canceled i was charged for it, i only recently went through all over the invoices and statements, and only noticed it now, how many times i didn't, when i do online shopping i want the piece of mind that i pay the price that's advertised, who wants or have the time to double check everything and basically do someone else's job, im definitely going to pay up my account and close it