A leather cream, balsam, or dressing may help to restore some of the colour loss. If leather is in the sun part of the colour loss is due to the loss of the natural oils from the leather, this is what keeps the leather flexible & prevents it cracking so oil is one of the ingredients put into comercial products for looking after your leather furniture.
Or try a coloured shoe cream or polish. Watch out though if it's not exactly the same you may end up doing the whole suite! lol.
Also, the colour may come off on your clothes if you don't polish it off properly.