Look for an update uninstall and reinstall wifi on off shut phone off on force close the app clear cookies cache. Those are the normal fixes if you still have a problem after doing those it could be on ibottas end and to wait a few hours/a day if still having problems you could be locked out and will need to put in a ticket to get unlocked.
My walmart page on the app doesn't have the headers such as any item, dairy, meat. I can look at my list and search for offers but I can't just scroll through any of the offers. Been like this since this afternoon.