kJams can now optionally use a new Licensing system called "Paddle".
When you run kJams with an active license, it will ask you to convert the license, just follow the steps and it will be done for you.
One thing to note however is if you use professional music streaming services from Karaoke Cloud and/or Party Tyme, you will have to re-download the entire database.
More info here.
You can cancel this for now, but it will be mandatory very soon, please update as soon as you can.