Not a BMW mechanic, but assuming you're speaking about the gap between dash and screen, unlikely to cause a problem. But parking tickets falling down into this gap sometime cover the chassis number usually visible on the nearside. Bane of my life as a MOT tester !! Often the other chassis plate is in a slightly inaccesible/awkward location.
I've had success removing them with a piece of wire hooked on the end. Also sticky tape may work. But it will be fiddly, you're unlikely to do any damage however, trying to retrieve it with the above methods