If you can see video on your phone coming from the Dash cam that would prove you are connected.
On the phone you press the red button to stop the recording.
It will take perhaps 10-30secs before it stops.
You should then be able to get into the menus on the phone to control and set the Dash cam.
I found it is a bit slow for some options. Waiting a little longer might make the difference.
I assume you are running a newer version of Android that the software is happy to run on.
If that doesn't work I've run out of ideas.