OP, gotta go with 4831 on his..."Why are you FL resizing new LAPUA brass????"
Folks, I am quite sure that lube is not the issue here. The issue is that sometime in the past week, the Lee dies went from sizing properly to scoring the necks of the brass quite deeply.
OP, I have some concerns as to cleanliness of your brass. I am seeing wisps of fibre on the first pics, even on the new brass case. If you cannot keep the brass clean, it is going to impart that same dirt into the lube inside the die, that is going to allow any microscopic shavings to adhere to it which in turn will start shaving off larger pieces of brass, which will get stuck in the die, which will shave off larger pieces and so on until you get an inoperative die.
I would follow Banished's advice and really clean the bushing. There is no problem with Lee dies that Lee won't fix, even your own stupidity, guaranteed.
I have a dozen or so sets of dies, most are Lee, several RCBS, some Hornady, and even a Redding. I haven't seen this type of damage in any of my dies, but I keep my brass SUPER clean and clean the dies out after every 500 reloads.
I would also remove the decapping pin and try to resize that way to see if the mandrel is squeezing too much. Is your neck brass too thick? This will help determine that.
If you decide to trash your dies, send them to me instead, although postage from AFRICA is quite a bit.