Watching U-verse TV

We've been using Samsung Smart TV remote to operate our TV for the last year. After  3PM , Oct 4 we couldn't change channels, or use any other dvr box function. Long conversation with the U-verse was useless, as they refused to acknowledge there is a problem and insisted on us using the AT&T remote.

When recording shows for later viewing and rewinding live shows, the screen freezes then skips ahead, losing part of the recording. I've called and tried to correct this with an agent by telephone at least three times over the last few weeks, only to have the problem resurface. How do I get a techn