You mean it won't come off the gearstick lever, or you don't know how
to go about removing it??

If it's anything like my 306, you have to unclip the the bottom of the
gaiter first where it meets the centre console, then lift the gaiter up
over the gearstick, then cut through the plastic tie wrap that holds it
onto the gearstick - you'll probably need a flat-head screwdriver to
prise the bottom of the gaiter upwards  - the gearknob will then pull
off - it takes a lot of strength and pulling, but it does eventually
pull off - I can't say if the 206 is the same as the 306, but wouldn't
imagine it's too different.