Can't submit asset pack to asset store.

Hi I have a particle system pack I want to put on the asset store, I get through everything I have to do to put it on but every time I go to place the icon, small, big images it gives me the error below. It’s my first time so please help, and I have followed the tutorial on the unity website on how to do it, and I do everything he does and it still doesn’t work. Please Help.

Error adding key image

Could not create package: Error receiving response
from server (403): The remote server returned an
error: (403) Forbidden.

edit your publisher account
web url must be something like this

You must have the full website url in the website space. Example: https://yourwebsite.com. and any other stuff it includes.