I had the exact same issue and just figured it out. Over the years I've had this software installed on several of my computers and there is a limit to authorizations. I have to go into my account https://line6.com/account/devices/ and deauth some old installs I don't use anymore.
Once I did that I started up reaper and Helix Native came right up. Hopefully you're running into the same issue as me and this will take care of it for you.