Try these steps to troubleshoot the issue.
Check you're using the latest app version of BritBox.
If the error message includes "this content is not currently available on this device" or a "manifest", it's likely that you're using an outdated version of the BritBox app and need to update. While most devices will automatically update your apps for you, you may need to update manually from time to time. Find out how to update your app.
Check if the error message appears when playing other episodes or movies.
Try playing a different episode or movie. If there's no error messages and you're able to watch without a hitch, it's likely there's a glitch we need to fix. Contact customer support and include the error message along with the specific episode or show, and we'll get it sorted.