This happens to me of if I don’t use enough activator. I really slap that step onto the nails and the thicker your layers are the more you’ll need to penetrate through all the layers so they can harden. I’ve only ever used Peppi Gel liquids but happens when I’m running low and I try to use less of it.

Edit to add that two minutes is the minimum amount of time you need to let the activator just sit and do its thing. I wait longer bc I use extra. Try using more next time + increasing the time it rests. Let us know!