mate i had the same problem with sensi skunk .... i found i had the cut the N down about 5 days before taking cutting and a good flush of the pot about 3 days before. cut ur cutting square off and straight into cold water , then 45 it and into the water again , then into ur rooting hormone and into ur rockwool or soil. when u put it into ur propagator cover the prop straight away, only take the lid off to add another cutting . i found this was the only way i could get them to take , i also use a small biece of carpet on the bottom of the prop which i would wet , i think this helps the cutting look for moisture.