It is possible that your device goes on standby mode during a WorkLink call mainly due to the setting of your device in response to inactivity.
The session will be disconnected if your device goes on standby mode for more than a minute. The app will attempt reconnecting and will be successful if the device becomes active before the disconnect.
To avoid a disconnect, adjust the standby mode setting of your device to allow the device stay active through out your remote assistance session.
Ensure your device stays active by occasionally tapping the screen.