Hi. Sorry you’re experiencing this.
I’m unsure how or why this might have happened on your site, but it sounds like you need to access your server files via cPanel’s File Manager, SFTP, or another method and then delete the event-tickets and/or event-tickets-plus directories.
Once that’s complete, please re-install both. You’ll need to visit https://theeventscalendar.com/my-account/downloads/ to get the latest version of Event Tickets Plus.
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Deleting The Events Calendar or its add-on plugins will NOT delete any of your data if you delete it via the WordPress plugin manager because that’s how we’ve decided to code our plugin.
FYI: deleting <b>any</b> plugin via FTP or cPanel’s File Manager (i.e. deleting just the files from the server) will also ensure a plugin gets deleted (if you delete the entire plugin folder) without removing any data from the database. This can sometimes be helpful to know in cases where a plugin <b>does</b> run an uninstall routine to delete data (again, our plugins do not run such a routine at this time and probably never will).
You can also see the difference when you click to delete a plugin, like this.