I am having exactly the same problem. I have power cycled the Roku. I have power cycled router. I have unplugged Roku Ultra, the plugged it back in. I have removed channels and added them back (if I was able, I can't even find Amazon Prime now...).
The ONLY streaming service that works is Netflix. Hulu, Prime, Disney Plus, Spotify, HBOMax, nothing works. I was able to remove the Hulu and add it back but it just times out and says there's no internet connection. Roku says there is. Other devices are getting internet.
I have signed out of the services I was able to load and went through a huge pain remembering passwords to get back in but still the services do not work. AND PRIME... I both logged out in the services, and then did the code to get back into it. Restarted. Unplugged, TV on off.
THIS HAS TO BE A software update issue. Netflix works like a well oiled machine.
I read some people have been dealing with these issues since early October, but mine started on 11/17, like so many others here.
Someone on another site said they logged out of their internet completely in roku and then logged back in and it worked. I have not tried that, and another said remove SD card and put back. I don't even think my ultra has a place for an SD card, which I see some new users with newer models are saying, but mine is many years old. It has always worked just fine, when our Samsung "Smart tv" started being stupid and couldn't connect to the internet.
All the menus load extremely slow... even system settings. Even trying to use options on a service title takes at least a minute or two to load up, if it ever does load.
How many ways do your users have to tell you that your latest update is a nightmare before you acknowledge a HUGE problem. I see some forum employees are saying it's a 'services' issue.... did you not tell them you were updating? Why would prime not update it's own app for your services on the weekend it's HUGE Wheel of Time series is premiering??? Makes no sense whatsoever.
I pay for several services within Prime and I can't get to them either. You need to fix this issue asap. Otherwise me and a whole bunch of your other customers will dump you for a device that works, AND will tell the world what a piece of **bleep** your company has become.