xfinity streaming app--downloaded shows not playing back

I've been having difficulty for the past 3-4 days playing back downloaded shows on my Galaxy S7.

My phone works perfectly well in every other respect.

THe xfinity app streams fine. It will download shows. But when I try to play back a download, I get the three dots for about 20 secs and then it says it cannot play back at this time.

I've uninstalled the app, cleared the cache, turned off the phone completely, reinstalled. Keeps happening.

But I just tried to download and playback a show on my Galaxy Tab 2, and it worked fine.

Any thoughts?