If you experience the 'no sonar readings' issue, first of all, you should check whether you have the latest version of the Deeper application installed or not. That can be checked by going to Google Play/App Store. Updating to the latest version of the application should help.
If updating to the latest version of Deeper app does not help, please try restarting the application as well as the phone and connect to the Deeper again. That might help to re-initiate the scanning process and the Deeper can start delivering the readings.
In case none of these methods help, please contact our customer support team at firstname.lastname@example.org or open a new ticket.