Upload 3d model for selling

good morning I am trying to put my 3d models up for sale and thus become a seller on the site, but this is denied me. the reasons for the declination are generic and do not allow me to understand where I am wrong.
I am working with Rhinoceros for modelling and Keyshot 11 for rendering the models, I have followed the instructions on the site for these types of software, but the result does not change. The models on my profile at the moment are loaded in .usdz format and this allows to see well both the materials and the textures applied. I have also sent several emails to the support centre to help me in troubleshooting, I follow their instructions step by step, but the thing does not change: I am not accepted as a seller.
can someone help me define a correct workflow that leads to the upload of an acceptable model for the sale.
thank you in advance