WARNING!!! Don't ride on them. They may explode on you.
Eh not sure that's a great piece of advice there..
I would guess based on your description so far that if you are rubbing on the shock, your lowering kit installer didn't put the shock bolts in right. A well known trick is to turn them inside so the thread points inward.
But these are guesses...without pictures thats all they'll be.
Take at least 3 photos:
-from behind the truck down the side so we can see the wheel to fender
-from behind and underneath, so we can see the shocks
-from one side, underneath, take a picture of the other side
B