That’s because the Mini 4 Pro is not campatible with Litchi.
The Mini 4 Pro has waypoint capability in the DJI Fly app.
(You don’t have to turn on the drone to make a waypoint mission).
If you still want to use the Litchi Hub, you could try this utility from @wesbarris:
It works with the Mavic 3 series, the Air 3 and most likely also the Mini 4 Pro.