When you purchase the ALICE app for the first time, the General and Medical categories are included at no additional cost. However the rest of the categories need to be purchased individually via a one-time in-app purchase. Look carefully at the category name, you will see a lock icon next to it. If it's black and the lock is closed, this means you have not purchased that particular category and need to enable it by an in-app purchase.
If the lock icon is green and open, this means you previously purchased that category and can use it anytime.