How to remove a Private theme from OctoberCMS platform?

How to remove a Private theme from OctoberCMS platform?
Because I am now using composer.json to inclide plugins and themes in my client project.
thanks because it blocks me to use the composer.json method.
I have this error:

..but theme author/themename form composer repo (https://gateway.october.cms) has higher repository priority

I only know that this works with plugins, but I think you should be able to remove it in the project settings on the OctoberCMS website (Account → Project → Themes Tab → click the X), and then do a php artisan project:sync in your root folder. But create a backup first, removal of the theme might remove other dependencies if they are not locked in through composer.

indede, I detached the theme from the project on the OctoberCMS website. But I didnt run the command project:sync before trying to add the theme again via composer.json. might be worth doing indeed, thanks for the suggestion