I'm posting this in hopes people see it, and get the help they need. It seems like a lot of people are still having this issue. I found this while digging for a fix, it worked for me. I hope it works for you too. (Credit goes to jr9650 for the fix)
Its a pretty simple fix
1. First go to the app, DO NOT OPEN IT. Instead hit start on it.
2. This should pull up a menu with sevrel options, scroll down to manage app
3. This will take you to another menu with more options, you now want to scroll down to saved data
4. Lastly, this will give you one option, delete all. Hit it, and try watching something after.
I really hope this helps, this problem was bugging me for along time