Hi @virgojoe,
sorry for the inconvenience.
I’ve understood why. It’s because of a bug in the plugin. When you try to delete it, it triggers a fatal error.
I will fix it and publish a new version soon.
I suggest you wait for the new version. When the new version is available, update the plugin, and then you will be able to delete it.
Take into account the new version will be published in 1-2 days.
If it’s very urgent, you can delete it also now via FTP, but you will need to manually remove also all the folders that look like wp-content/plugins/pr-a3c0ed79….
If you wait for the new version, during the deletion the plugin will automatically delete those folders.
Let me know if something is not clear.
Have a great day!
Jose