Yuck. Off the subject a minute, I had a client who would only come in for a backfill when her nails were about to fall off. She also worked with kids so her nails got really battered as she was in water & stuff, plus they always had paint around the edges where they had lifted. It was taking me twice the normal time to do a backfill as my other clients but I was charging her for just a backfill. In the end I told her she'd have to start looking after them & come in more often or I'd start charging her for a full rebalance every time, as that was really what she was getting. Funnily enough, straight after that her nails miraculously stopped lifting & she never had paint under her nails again. The point is, how has your client been looking after them at home? If she has paint under them she's clearly not treating them well! I would double & triple check your prep as this is the likely cause for them lifting away but also make sure you've given suitable aftercare advice so she knows how to look after them. HTH