Is it possible to mint multiple NFTs at once via looprings "advance create" function? I have 2 folders with images and metadata on Pinata but just receive the message "no content" when I paste the CID from my metadata folder. If I paste the CID from 1 of the .json inside the folder I'm able to mint the corresponding image. Is it not possible to mint in bulk? Won't there be a huge fee if i mint every image one at a time?