The voice assistant needs the microphone; showing it things needs the camera. The phone asks the first time. If you said no:
On iPhone: "Microphone access is off. Turn it on in Settings > 1krNote." or "Camera access is off. Turn it on in Settings > 1krNote.". Open the iPhone's Settings → 1krNote and turn on Microphone or Camera.
On Android: open Settings → Apps → 1krNote → Permissions and allow Microphone or Camera. 1krNote also asks again when you start a voice chat.
"The microphone could not be started.": another app may be using the microphone (a call, a voice recorder, a video app). Close it and try again.
Using the camera in a chat: tap Camera on first, then Look to show one picture, or turn on Live: on to stream. "Enable the camera first to stream vision." or "Camera not ready. Enable the camera first." means the camera wasn't on yet: turn it on and wait a moment.
The microphone is only used during a voice chat or a voice memo, and the camera only while you turn it on.