You own a neXt v1.x license and have probably overlooked the update note on the download page for the v2.x.
After 9 years with many free v1.x updates, we have updated to version 2. You can upgrade your v1.x to v2.x license at an additional cost. Or of course reinstall the old version. The update link and the previous version can be found here: https://www.cgm-online.com/rc-flight-simulator/download_e.html
It's not just a minor update. With a v2.x license you will continue to receive the monthly updates.