tuch-up paint question

[kam472]

i just tuched up my V yesterday .It was nice sunny day. I cleaned all stone chips with sanding pen, start putting paint lightly to build up above the surface to wet sand it later ,etc, ...question is how long does it take for the touch up paint to harden? Seems like it's been more than 24hrs and its still not hard enough. Night was a bit chilly though but noot too chilly. Should i wait a bit more or just buy new touch up pen? With what should i clean the paint off if it does not harden?? Any thoughts? Thanx in advance!