To everybody that Is confused on how the movie ended and how she got all the cash, let me explain. That was a flashback of Joy when she was still in Nigeria (before she travelled to Austria). She was working as a fake cash seller. So in Nigeria parties/weddings or events you see a lot of the guest spreading fake cash as a form of celebration. So you saw that the lady at the party was buying the cash from Joy. so at the end, Joy gave some of her earnings to a connection guy to get her to Europe