Exact same happened to us, https://skymarktrading.com deleting the directory only made it worse.
After turning on all features (yes, I know, dumb move, I know better) I was logged out and when prompted to login again it says the user wasn’t found.
Prior to deleting this plugin’s directory, the site would not load at all, even the admin user had been seemingly removed. Very, very, odd behavior. We’re still not back up yet, all sorts of errors now being thrown after deleting the directory…….
