If you're using an Apple M1 Silicon Mac unfortunately there is no Maestro software compatibility for Duet USB currently.
We don’t have a date for this compatibility with apple M1 mac hardware as yet but you'll be notified as a registered user as soon as this becomes available.
On an M1 Mac Duet will still be detected as an input and output device in System Preferences > Sound when connected but you won't be able to load maestro to change your input type.
If you have maestro installed on another intel based mac you could connect to this and change your input type and this should retain these settings when connected to an M1 Mac.
Otherwise there are no workarounds to change your input type on an M1 mac until a new driver for this is released.