Uninstall WP Staging plugin

Hello,

I want to uninstall the WP Staging plugin because I don’t need it anymore, but I can’t seem to do it.
On the “Installed Plugins” page in WordPress admin, when I click “Deactivate,” nothing happens.

In the WP Staging plugin’s admin interface, I still see a staging site listed as active. When I click “Delete,” the deletion is performed and confirmed without error, but the staging site still appears. However, the files and data no longer exist.
I followed the steps at https://wp-staging.com/docs/delete-staging-site/, but it’s not working.

So I’m stuck.
Could you help me uninstall WP Staging?

Thank you in advance for your help!