Why can't I connect to the camera's Wi-Fi after I paired my iPhone again?

The password for your camera's Wi-Fi is randomly assigned each time you pair. So after you unpair, you need to press the information mark from your iPhone's Wi-Fi setting page and select 'Forget this Network'. And then connect to the camera's Wi-Fi again, long-press on the box where you enter your password and select Paste. After the camera's Wi-Fi is connected, go back to the App, you should be able to see that you have successfully connected to your camera.