Pandas with aircon or climate have a notoriously difficult to access cabin (pollen) filter.
it is to be found just to the left of the clutch pedal and is vertically orientated.
An elongated, rectangular cover has to be removed. The bad news on earlier cars is that this panel is held in place by 8.5mm bolts, an unusual size for which you may well not have a spanner or socket. My 2008 Cross doesn't have bolts holding the panel in place. However, once the panel is removed the old filter is tricky to remove and similarly the new filter is difficult to insert. Depressing the clutch pedal helps, a friend to do this for you helps even more.
Search this forum and you will find pictures that clarify my description, I'm sorry but I don't do photos at the moment.