I cannot see my audio device

How do you do. I’m a beginner. Thank you.
I have connected the Ipad to the UR22C. This is my first time, so I’m using Cubasis LE 3 for now. USB recognized and tried recording a simple drum sound and a synth sound on two MIDI tracks. When I try to record a guitar on an audio track, a small recording sign on the audio track rotates, but the waveform does not appear.
I can hear the guitar sound with the effect of DspMix UR-C from the headphones.
I searched a little on the net and selected SETUP→ lower left Audio at the top right of the Cubasis screen, but I can not select Audio Device, it seems that it is not a basic setting.
I think that it is a basic setting operation, but I would be happy if you could advice.
Thank you very much.

Translated from Japanese by mod

Hi @amitani0221,

Thank you for your message and welcome to the Cubasis forum!

Please have a look at our Getting started with Cubasis tutorial, to learn how to use the app to create your tracks in no time: Getting Started with Cubasis | This Is What You Can Do with Cubasis - YouTube

Please learn more how to use Cubasis with your audio interface, in the Adding Audio Tracks chapter of the clip.

Please let me know if this helps to resolve your problem!