Fixed a bug with the database initialisation and also done a few more code improvements.
I also improved the backupcode command where you now can click the chat message to copy the backupcode to your clipboard instead of reading it from the chat message.
I got the time and motivation to work on this plugin again and updated it to 1.21. I also improved many things code as I am refactoring it (I am still working on this not everything is done!).
Also the security is improved and also the plugin now uses a sqlite database to store the user data.