Please help. I'm struggling with gel nail extensions. They never seem to last longer than 1 week I'm using the NSI gel and prepping thoroughly. This is my nail after 10 days and the whole extension has literally popped off
Ok, Your front form looks good, they look a lovely shape.
Your side view shows that you are making nails that are very flat, there should be a bigger apex than what you have particularly due to the length. You should be aiming for the thickness of 2-3 credit cards in the very centre of the nail and have it blend into the natural nail around the cuticle and side walls and about the thickness of one credit card at the free edge. Because your nails are lacking an apex they have no strength, if you look at the nail that came off you can see damage across your stress area where the apex should have been, you have hit the nail and it couldn't take the pressure so popped off.
The barrel view shows that they are an even thickness so thats good, but they could maybe do with a little thinning out at the free edge and making sure you get that apex slowly built up to the centre for a more natural looking enhancement.
It looks like you haven't done any cuticle work at all, I can see a lot of excess cuticle around the nails, this will cause lifting. I can also see that you have hit the cuticle area with the gel in places, this will also cause lifting.
Hard to see, but some sidewalls look flooded a bit.
The gel needs an apex.
It doesn't look like you fully covered the nail in top coat.
What's the state of your natural nails and what is your prep routine?
The nail where it came off looks damaged to me, and this will affect longevity.