If the system is new, it can have factory-residue on the lace...they spray the hair with silicons to add shine ..this can get onto the lace and prevent good adhesion ....when you take it off and wet it [ by immersing in a basin of water] apply shampoo directly to the lace and leave it for a few minutes before rinsing it off ....... sounds like you may be applying the glue a little too sparingly ....try slightly more [3 coats] and a little more thickly .... you should leave each coat to ` cure` for longer than a minute....it`s a balancing-act ...... you don`t want to plaster it on too thickly, but you need enough to actually ` grab` the lace sufficiently to hold it in place for however long you want.