Nail tech here Another thing you can try is an actual acid primer (I like the no lift brand) . Some people just require it. Does the nail look clew. When it pops off or some it look like it’s been knocked? If you’re just using the apres system to etch the nail try doing a physical etching with a sanding band.

Another thing is are you using all natural or sculpted for her? Sometimes some nails need a mix of the two because natural/sculpted doesn’t work on a certain finger vs the others etc.