Cant select version when making new installation

For a server i wanted to create a new installation with the version 1.15.2

Sadly, when I attempted making the installation, nothing happened. I could put in the name and select the icon, but when I clicked the version tab, nothing happened. I couldn't make a new version because of this. I tried fully reinstalling the launcher, and logging out and the in to my account, but with no luck. I could find I solution, but I didn't fully understand it.