Possible problem with new formula Minx?

I had a new client in today for Minx toes, all went well, all the Minx seemed to be sealed perfectly, wrinkle free etc. I had a message from the new client four hours later saying that one of the Minx has come off completely, and one is partially off.

I prepped for the Minx as I usually do (which normally lasts at least 4 - 6 weeks):

- CND Foot Soak (whilst doing client record card & choosing Minx)
- Dry feet & remove any old product
- Cuticle tidy (using Bio Sculpture Gel cuticle...

Possible problem with new formula Minx?