I sometimes met this issue. Cache and low internet connection could lead to this problem, as the page remembers items of the last restaurant you opened. However, it just flashes in second and then automatically reload the right items for current store.
Not only items, the addresses have the same issue, even after you delete addresses of one customer, following this thread: https://discuss.foodomaa.com/d/944-how-to-delete-saved-addresses-of-all-customers-to-force-declare-new-address/16
But then that customer still see the deleted-addresses in saved list (just in 1 or 2 seconds and disappear, if they click before the address disappears, it will re-update into the db again)