Amazon Prime on smart TV - Internet connectivity issue

My wife has Prime, and we watch it on our Sony X800G smart TV. We have Xfinity Internet. When we select the Prime app, we get a message saying there is an Internet connectivity issue. After spending time on the phone with Xfinity, we no longer get the message – just a black screen. (The YouTube app says it cannot connect.) Why can we not connect?

Xfinity did say they were going to run some diagnostics that would take 30-60 minutes, and I’d get a text message. I hope they use the cell phone and not the landline.

I got a satisfaction survey on my phone, so I retried. I got YouTube and Peacock, but not Prime. I tried a Force Stop on Prime, and it is working now.