Which version of Roon are you running?
You may know that release 2.0.26 split the formerly single ‘app’ into Roon Server, which is self-standing and runs independently; and Roon Client, the equivalent of the old ‘Roon’.
Could an update process which you started but perhaps did not finish, or have yet to apply, be causing this?
If you do have the latest version (and the very latest build was released on 2024-01-10), what happens if you actually restart your Mac? If you have Roon Server in your login items, and then restart (as opposed to sleep and wake) that may start the necessary processes.