The Pollen filter is located 'in the glove box' or at least behind it. Open the glove box, unscrew the inner box retaining screws, remove the inner. This will reveal a plastic sliding clip, slide and open the flap.
Behind the flap you will see one of the pollen filters, slide it to the right and remove, then on the left of that one is the second, slide it across and remove.
I recommend you have a vacuum cleaner at hand to catch any excess dust / debris.
Replace in reverse order.