A. If items are disappearing from your shopping bag, check if there is a time limit for holding items in the cart. Some apps automatically remove items after a certain period. Try adding items to your wishlist instead, as they might be saved there for longer periods.
B. Ensure that you are logged into your account when adding items to the cart, as items might not be saved if you are browsing as a guest. Regularly update the app to fix any bugs that might be causing this issue.