Character mistake: In the very first scene in the film, the magazine covers are flashing up. There is an article called 'How to get a better bod in 5 days.' If you read the beginning of the article it says 'It Can Done.'
Continuity mistake: In the scene where Ben just ran down the fire escape to Andie, she walks away waving. In the shot of her front side she's waving with her right hand, and then in the next shot (a rear shot) she has her left hand up. (01:08:38)
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Answer: Because he is working in a jewellery market for his advertising company.