Inconvenient website cancels out online convenienc

We do our groceries shopping online (the Smart shopper account is in my husband's name) and at the beginning it was really convenient, but the website has just gotten progressively worse. Problems we've been having include: can't log in, won't load a saved list, won't save a list, won't check out/just goes to an error page when you try to check out. For the last two weeks it lets you do your shopping, you check out and suddenly multiple items (and sometimes the delivery cost itself) is causing an \error\" and those are removed. You end up having to check out without all the items you wanted and go to the store anyway to get them. Other issues include: you can't search within a sub folder, the search bar doesn't appear on tablet screens, the search algorithm is terrible, loading times are long, sometimes the screen just freezes when you add an item, sometimes it only tells you an item is unavailable once you check out, you can't empty your trolley in one action, when you select to display all items in a specific order it doesn't keep those settings like that from search to search so you have to enter it again. Some items are in inappropriate categories and there are spelling errors."