I was able to fix not seeing live stream in Chrome: go to where lock at the beginning of the address https://cloudcam.amazon.com/? is. Click on the lock. click on site settings and change CAMERA to ALLOW. (Default was set to ask. Change to allow.) Everything else is set to default.
I have also faced that type of problem when I primarily used chrome. I could not get Manage my browser.
I tried clearing cache in Chrome, restarting cameras, logging in and logging out - still, get "unexpected error". At that moment, I got a solution from online. I used firefox, Its work so nicely. If you want to get more details by clicking mozilla firefox cant connect server. This one can properly guide you.