I just spent 2 hours with Samsung support specialist remotely connected to my TV trying to fix the issue, but they were not able to fix it...
They also just tried every workaroung mentioned here but to no avail.
Not sure if I can post this website address for AT&T.
You can get a chat or call them.
Ask how to block a website and then unblock it. They really don't have any good info on that. All I found was blocking a mac address. That would probably work. But its free help and safer for you to call or chat with AT&T. I would hate to mess up the system and cause a problem you don't have now! Sorry but I'll still try to help.
I'm having a problem with my Samsung Smart TV. Downloading Apps. I have a fix that works. What the fix is to block a URL
(that's U. R. L. in case You don't know)
Then unblock it.
You will have to follow the directions I posted already.
I would just read those to them.