Oh wow! I’m not sure. I bought it preloved and she had it folded when it was sent..... it’s in such excellent shape but I can’t stand the crease!Could the crease be caused from a purse organizer. It looks like the line would be the height of one. When there is nothing it try also stuffing it with air packs that you get with packages to maintain shape. Also, you could try sitting it in direct sun to warm up the sides to get the crease out. I’ve heard of people also using a hair dryer to warm it but I’ve never tried that myself.