Unsatisfied online frequent shopper

Almost 3 times a week if not more checkers doesn't have the items I order on the 60 60 app. Why advertise it then??? They don't have bread some days or even bananas. I was told my solution is to chose alternatives for each item. That's ridiculous because the point of this app is to make the buyers life simple. Yet I have to keep reordering. It's annoying and time wasting. Why advertise pots you don't have only then for me to wait 2 days for a refund. I was called n told I purchase alot yet no rewards or vouchers. Please learn from other stores and don't advertise what u don't have. Don't tell me to choose alternatives on 10 items. Lastly if one item is unavailable its fine but give me time to choose an alternative don't complete shopping.