Hello, Eduardo,
Take a look at `info guix menu-entry`, that addresses the issue you described.
If I don't incur in any mistakes, you can fix by making your
system-configuration
like this:
```scheme
(operating-system
...
(bootloader
(bootloader-configuration
...
(menu-entries
(list (menu-entry
(label "Debian GNU/Linux")
(linux "/boot/vmlinuz-4.19.0-27-amd64")
(linux-arguments '("ro" "quiet"))
(initrd "/boot/initrd.img-4.19.0-27-amd64")
(device (uuid "UUID=6fe52b2e-dd43-4a9b-b5e9-4c05fdc5975f"))))))))
```
and then running guix system reconfigure.
Hope that helps,
Luis Guilherme Coelho
