Sounds like it's doing what mine has at times..
The trigger gets to the rear of it's travel before the
striker is released. In the case of mine, I think part of
it was the razor sharp edge on the striker. It seemed to
keep it from releasing if you did a slow pull.
This will usually not happen with a "fast" pull if this is
the case. With mine, it's only when doing a slow pull.
What I tried is very slightly rounding the edge of the striker
so it wasn't so sharp. It seemed to help quite a bit.
Try slow and fast pulls.. I bet it almost never does it on a
fast pull. Thing is, I like to use a fairly slow even pull.. :/
Anyway, I think little striker/ seer polishing will likely cure
the problem. You might want to send it in if it keeps doing it.

BTW.. In the case of what mine is doing, it is not a reset
problem. When mine would do that, you could release the
trigger, and then try again with a fast pull and it would
fire no problem.
If it's doing what mine was doing, it gets right to the edge
of firing, but you run out of enough trigger range to the rear
to lower the seer over the edge of the striker, so to speak..
So it doesn't release the striker. But if you try again with a
fast pull, it will fire, as you are using more momentum to
get it to clear.
I imagine very slightly lowering the seer height would do the
same. IE: polishing it down a bit.. That would very slightly
lower the amount of trigger pull needed to release the striker.

Pardon my explanation.. I'm not really a gunsmith or even
play one on TV.. That's just the conclusion I came to when
mine was doing that. Slightly taking the sharp edge off the
striker seemed to do the trick in my case.