Get vrm to fbx into unreal

Hi iv made a character first useing vriod as a base as a vrm, I have then imported this into blender and added custom fbx sculpts from zbrush in as cloths and props, iv done all my retopology etc and set up by bone weights and everything, however when I export unreal or other programs are picking up the textures for the cloths and fist but not the body and I’m trying to work out why ? thank you