Does the issue only occur on Discovery Plus or across other channels installed on your Roku device?
Have you tried removing the affected channel Discovery Plus and then re-install again? If not, we suggest starting there. In some cases, removing the affected channel and then re-installing it may help. Restart your device before re-adding the channel back in to ensure the process is successful. We recommend doing this through the Settings menu by navigating to Settings > System > Power (If there is no Power submenu, proceed to the next step.) > System restart.
Many channels on Roku are maintained by the channel provider themselves. Since the error only occurs on the Discovery Plus channel, that's an indication that there's likely an issue within that specific channel that needs to be addressed with an update from them. We indeed recommend contacting Discovery Plus Support to report the issue and get help.