Adding a new website in blog cutter you have to install blog cutter api plugin to complete authentication with your website.
Blog Cutter Plugin Install
You need to install Blog Cutter’s own plugin on your site for REST API authentication.
You can download the plugin from here
Follow the steps below.
First go to Upload from plugin then Add a New Plugin
Click Upload
Click Install the downloaded plugin from Choose File.
Activate now
Once the download is complete, activate the plugin by uploading it from Upload.
Your work is done.