We’ve recently updated our Addendum to the Terms of Service surrounding Kobo Plus. You’ll be required to re-accept this updated Addendum. Here’s a link, for your reference:
We’re currently experiencing a bug where users are unable to accept this. Please ignore the pop up window for now. We’re working on fixing this and it should be resolved in the coming days. You’ll be able to opt your titles in to Kobo Plus once this is fixed.
This error shouldn’t prevent you from publishing a new book or making any changes to an existing one. It also doesn’t affect titles currently in Kobo Plus. If you have any trouble with it, please submit a request and let us know.