I agree with the previous post in that lengthening the philtrum columns can be aging, but there are certain instances that this is desired. Without seeing a picture it is hard to make the recommendation. I will say that at times a small amount of neurotoxin (Botox) at the base of the columella can help you achieve this effect if elongation of the cutaneous upper lip is truly what needs to be accomplished. This will also lift the tip of a "witch nose." Ideally an injection in this area would be combined with lip fillers to maintain a balance of the lower face. Thank you for your question and good luck!
The best way to do this is with filler to expand the lips. Lengthening the philtrum is an aging phenomenon and is not desireable. I would try this first.