Hello Steve,
I've got Lee 380, 9mm X2 sets and 45acp dies and no problems with any of them.
I would suggest taking the powder thru/flaring die apart and clean it well, then do the same for the seating die. Nothing fancy, just to clean and get any old grease, oil, wax or crud out.
The walls of the 380 are pretty thin and deform easily. With my 380 dies I have a problem using the Lee Auto Drum measure with them, The return spring in the measure is strong enough that if the case is off center by just a small bit it will chip out a small piece of the case mouth while feeding into the die. I know this because if I remove the Auto Drum and put a Auto Disk in the die the problem immediately disappears. I also talked with another friend that was having problems with his 380 dies also, He too took them apart and cleaned them and then carefully reset each one and his problem went away also.