Having Trouble With Exporting from Blender to Unity

I’m trying to submit items from blender to unity for ZEPETO but every time I do it, my clothes item looks disoriented and spiked. I don’t understand it very much and how to fix it. Can you help me understand the problem so I don’t have to worry about it? I would like to share with you the images and files but It says new uses cannot add files or images. Ill do my best to share and try all different options.