Is this a "Samsung" app, or someone else make it? This may be the fault of the app creator. When opening the app in the app store, there should be an email address used to contact the creator in case of issue. This is really the only place to deal with this. The Samsung app store on their connected devices like TV's and blu-ray players, is no different than the one on your smart phone. Do you connect your phone mfg when an app fails; Google if an android OS phone? No I'm sure you don't. With all apps regardless of device, the only person that can fix it is the person who created it.
When I try to watch the MLB app on my Samsung TV the picture is either completely distorted static or I get 4 distorted copies of the same game in each corner of the screen - with static in-between.
After closing and reopening the app a couple times I performed an update of the app; no improvement.
I was going to delete-and-reload the app but it cannot be deleted (not one of the options shown for that app).
I checked the same MLB account on my computer and I am able to watch games normally there.
I have successfully used this app on this TV many times in the past.
So, now, I am unable to use the MLB app, and I am not able to fix it.

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