Streaming app is low resolution on Samsung Galaxy A9+ tablet

The Xfinity Streaming app is low resolution on my tablet. It was fine at first but went to an unwatchable low resolution.  I tried factory reset on tablet and re-download the infinity stream app and it's still low resolution. The tablet plays all other streaming apps perfectly. It's just xfinity stream app that is unwatchable. I have tried all the online tips and nothing is working.