Diagnosis
Your camera is having trouble sending a strong enough video stream back to your phone. This is usually due to insufficient upload speed from your internet provider or a weak Wi-Fi signal at the camera.
How to Fix It
First, test your internet's upload speed using a site like speedtest.net from a computer near your router. You need a consistent 1-2 Mbps upload for reliable Live View. If that's low, contact your ISP. If your speed is fine, improve the camera's Wi-Fi signal. 1) In the Ring app, go to Device Health > Signal Strength. If it's Fair or Poor, that's your culprit. 2) Relocate the camera or router, or add a Wi-Fi extender as mentioned in the previous fix.
If That Didn't Work
Too many devices might be sharing your Wi-Fi bandwidth. Try temporarily turning off other video streams (like other cameras, smart TVs) and see if Live View works then.
Heads Up
The battery model uses a more efficient connection to save power, which can make Live View a bit slower to start than a plugged-in model. Give it an extra second or two after tapping.