Had the same issues as many of you are reporting. I followed someone’s post about updating Roku AND Restarting Roku. It worked perfectly. I was able to load the channel and all my channels that were not working started working again. Directing are on his post. Find it and follow all the steps. Hope this works for you.
@Romona didn't give us much to go on in finding that particular post out of the thousands and thousands on here.
I've posted this in the past, perhaps that's what she was referring to:
In the past, I've found that when a Roku receives a major software update, it may not automatically update all channel apps that have new versions to accommodate the Roku update. Manually running an additional update check as soon as you receive the Roku update can make sure you have the latest versions of all your channel apps and prevent many update-related problems (Settings > System > System update > Check now).
And for good measure, I always restart my Roku afterwards via Settings > System > System restart (for a Roku TV it's Settings > System > Power > System restart).
Despite having had access to the Roku update as it was being developed, some channels may take a few days for their developers to issue needed updates, so a manual update check is a good first step when running into specific channel problems.