Hi jeydee,
Welcome to the Roku Community!
Thanks for letting us know about the behavior you're seeing with the Tubi channel and all of the troubleshooting you've done.
Please make sure that when removing a channel, it's important that you make sure to restart your Roku device before adding the channel back again to ensure a clean channel install. If you are still unable to resolve the issue.
However, If removing the channel and adding it back after you've restarted the device does not resolve the channel issue, I'd recommend reaching out to channel support directly to report the issue and request additional support. Many channels on the Roku platform are developed and maintained by the channel provider directly, and they'll be able to best assist. If other channels are working correctly, and you only experience this issue on that channel, that is likely an indication that the issue lies within that particular channel. In these cases, the channel provider will need to investigate the issue in order to help resolve it.
You can reach them here: Help Center (tubitv.com)
If you have any other questions or concerns, please let us know.
Best regards,
Mary