^ That looks to me like the setup for an analogue tuner. I don’t have time to look right in detail right now (have to go out for a while) but there should be a Tuner Setup menu where you can disable the analogue tuner, and make sure that the DVB tuner is switched on. This should then enable you to tune the digital tuner.
The manuals are still available from B&O support here: https://support.bang-olufsen.com/hc/en-us/articles/360041950191