Please note that when you activate the plugin in a new domain, your data may be lost. That's why you need to backup your Booknetic data first. To move the plugin to a new domain:
Go to Settings to Export Booknetic data;
Go to WordPress > Plugins menu;
Deactivate the Booknetic plugin on the current website;
Delete the plugin;
Reinstall the plugin on your new website;
Then Import the Booknetic data back.