I get this error with the ESPN app on both of my Rokus at least every other day. 90% of the time, if I deactivate the app from my satellite provider, then re-activate it, it'll fix it.
But to be honest, I get similar errors for about half of the Roku channels on a regular basis. The Fox News Roku channel is the absolute worst. It seems to lose my activation exactly every 2 days, and I have to re-activate it. Most of the time the Fox News app will pop up this bizarre error message about my cable Internet provider not offering that content, even though that's not who I ever activate it through.
I thought it was just poor programming in the Fox News app, but I get deactivated from other apps frequently, so I think it's just a flaw in the Roku technology.