After the installation, I was able to verify the installation as successful using “gvm-check-setup”.
The service starts cleanly and without error messages.
Unfortunately, when I try to access the GUI on the VM itself, I get the following error message:
Unable to connect - An error occurred during a connection to 127.0.0.1:9392
Regardless of whether with HTTPS or without.
The log is free of warnings or errors.
I moved this post to the Linux Distribution section since it is not related to vulnerability tests.
Which Linux distro were you installing to? Greenbone is only currently supported in Kali Linux. 
Thanks for moving!
I’am using the newest Kali version with all packages up tp date.
I just installed gvm on the newest Kali Linux 2024.2 VirtualBox image fully upgrade following the Greenbone’s Kali Linux native installation guide.
HTTPS is enabled by default on the Kali Linux native installation - so you cannot access it via http://127.0.0.1:9392, you will have to explicitly use the https:// schema. Secondly, after running gvm-check-setup everything was reported OK, but I was also not able to access the GSA via https://127.0.0.1:9392 immediately. All the services status reported to be active and there were no errors in the logs.
However, after running sudo gvm-stop and sudo-gvm-start again, I was able to access GSA on https://127.0.0.1:9392 successfully. I’m not sure exactly what was wrong, but perhaps you can try this and let me know if it also works for you.
Yes, I have now also reinstalled.
No idea why the WebGUI was not accessible.