This is the first time this has happened to me in a lot of orders on here.
I ordered what was supposed to be new Lego pieces.
I received used Lepin or other off-brand pieces. One stud on each piece is indented
where the Lego logo would go.
These people should not be allowed to operate on here. Go sell that junk on
fleabay.
I once ordered a few 100 used 2X4 bricks in any color for filler, and one piece
showed up as a mega-block. I tossed it in my off brand pile and pulled an authentic
lego piece from my bulk. I didn't bother the seller as it had the appearance
of an honest mistake on a low value piece.
Sounds like what you're describing is the whole order is off brand and not
NEW as advertised. This is a very different scenario, and the previous advice
given by other users is your best bet.